Matematika Ii Dio

  • May 2020
  • PDF

This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA


Overview

Download & View Matematika Ii Dio as PDF for free.

More details

  • Words: 31,927
  • Pages: 108
Viša tehnička škola Doboj

Vježbe Prof.Vesna Mišić

Doboj 2003 1

Matematika

Funkcija - definicija 2

Definicija : Funkcija je preslikavanje skupa A u skup B pomoću koga svakom elementu skupa A pridružujemo tačno jedan element skupa B. preslikava f : A  → B

Domen ? f( x) 1. y = g( x) 2. y =

f

A x

D : g( x) ≠ 0

f( x)

f

D : f( x) ≥ 0

B y

−1

Domen (područje definisanosti), Kodomen (skup vrijednosti ).

3. y = log f ( x ) D : f ( x ) > 0 4. y = arcsin x D : − 1 ≤ x ≤ 1

1 y=sinx 0 -1

π



y=arcsinx

Inverzne funkcije. f : A→B f : x→B x 0 30 si nx

° 0

° 1 2

x

0

arcsinx

0

3

f

−1

:B→ A

f

−1

:y→x

45° 60° 90 ° 2 3 1 2

1 80° 0

2 70° -1

360° 0

2 1 2 π 6

2 2 π 4

3 2 π 3

1

0

-1

0

π 2

π

3π 2



Funkcija f : A → B je : 1. Injektivna (1-1) ako f ( a ) = f ( b ) ⇒ a = b . 2. Sirjektivna (na) cio skup b ako je f ( A ) = B . 3. Bijektivna (ako je injektivna i sirjektivna). 4. Parna ako je f ( − x ) = f ( x ) za svako x iz A . 5. Neparna ako je f ( − x ) = − f ( x ) za svako x iz A ( ∀x ∈ A) , (simetrična u odnosu na koordinatni početak) . 6. Periodična s periodom ω, ako vrijedi f ( x +ω ) = f ( x ) ( ∀x ∈ A) . 7. Rastuća x1 < x 2 ⇒ f ( x1 ) < f ( x2 ) ( ∀x1 , x 2 ∈ A) . 8. Opadajuća x1 < x 2 ⇒ f ( x1 ) > f ( x2 ) ( ∀x1 , x 2 ∈ A) . 9. Ograničena m ≤ f ( x ) ≤ M ( ∀x ∈ A) , ( m < ∞, M < ∞ ) . 1. a b

1 4 2 5

c

3

Injektivna, ali nije sirjektivna 2. A

1

B 0

2

Sirjektivna ali nije, injektivna, f

3.

2 4

1 2

6 8 10

3 4 5

Bijektivna (injektivna i sirjektivna) 4. Parna

y=cosx 0 4

y=x2

5.

y=x

y=x3

6. y=sinx

7.

f ( x2 )

) f( ′ ) x f(

x2′ 1

x1 x2 a

Domen. 5

f ( x1 )

x1′ x2 ′

b

1. y = sin ln( 2 x − 3)

x x −1 + x2 − 4 2 x+3 ( x − 4) + 4 − 3 x − x 2 3. y = ln x+2

2. y = 2 sin + ln

4. y = sin π ( x − 1) + 4 − x 2 1. D : 2 x − 3 > 0 ⇒ x >

3 2

x 2

2. 2 sin = 0 ∀x ∈ R x −1 >0 x + 3 = 0 ∧ x −1 > 0 x+3 x = −3 ∧ x > 1 -∞

-3

1



x

+

x-1 x+3 x −1 x+3

- 0 + 0 + + +

I1 D : x ∈ ( − ∞ ,− 3) ∪ ( 1,+∞ ) x2 − 4 ≥ 0 ( x − 2)( x + 2) ≥ 0 x1 = 2 ∧ x 2 = −2

-∞

x+2 x2-4

I 2 D : x ∈ ( - ∞ ,-2] ∪ [ 2,+∞ )

6

2

x x-2

( D : I1 ∩ I 2 )

-2

+

- 0 + 0 + + +



-3

-2

1

2

D : x ∈ ( − ∞,−3) ∪ [ 2,+∞ ) x−4 x−4 > 0 ∧ ln ≥0 x+2 x+2

3. D :

x−4=0 x=4 x+2=0 x = −2

x−4− x−2 ≥0 x+2 −6 ≥0 x+2 x+2<0 I 2 : x < −2 D : x ∈ ( − ∞ , −2 )

x−4 ≥1 x+2 x−4 −1 ≥ 0 x+2

-∞

-2

4



x

-

x-4

+

x+2 x−4 x+2

- 0 + 0 + + +

I1 D : x ∈ ( - ∞ ,-2) ∪ ( 4,+∞ ) 4 − 3x − x 2 ≥ 0 3 ± 9 + 16 x1, 2 = −2 x1 = 1

− x 2 − 3x + 4 ≥ 0

x 2 = −4

I 3 : D : x ∈ ( − 4,1)

D : x ∈ [ − 4,− 2) -4

7

-2

1

4

4. y = sin π ( x − 1) + 4 − x 2 sin π ( x − 1) ≥ 0 0 ≤ π ( x − 1) ≤ π 0 ≤ x −1 ≤ 1

x ≥ 1 ∧ x ≤ 2 I1′ − 4π ≤ π ( x − 1) ≤ −3π − 4 ≤ x − 1 ≤ −3 − 3 ≤ x ≤ −2

-3

− 2π ≤ π ( x − 1) ≤ −π / : π − 2 ≤ x − 1 ≤ −1 x ≥ −1 ∧ x ≤ 0 I ″ 1

/ :π

-2

D : x ∈ { 2} ∪ [ − 1,0] ∪ [1,2] 5. y = x − 3 − x x−3 = 0

-1

0

x ∈ ( − ∞ ,0 )

I1

1

y = −( x − 3) − x y = −2 x + 3

y = −( x − 3) + x y=3

x =0 I1

I2

( 3,+∞ )

y = x −3− x y = −3

x y

0

2

3

-1

I3

0 I3

2

x ∈ [ 0,3)

I2

y = x−3 − x

x =3

4 − x2 ≥ 0 ( 2 + x )( 2 − x ) ≥ 0 I 2 x ∈ [ − 2,2]

3 y=3 3 y=-2x+3 3 y=-3 -3

1) Da li je funkcija injektivna? y = 3x + 5

5



8

5 3

0

Sirjektivna

2) Naći nule funkcije

(

y = ln x 2 − 3

)

D : x2 − 3 > 0 y=0 ln  1 = 0

(

) (

D : x ∈ − ∞ ,− 3 ∪

3 ,+∞

)

0 = 1 f = 0 ⇒ x2 − 3 = 1 x2 = 4 x1, 2 = ±2

-2

y>0

x ∈ ( − ∞ ,− 2) ∪ ( 2,+∞ )

y<0

x ∈ − 2,− 3 ∪

(

) (

3 ,2

− 3

3

2

)

8. Koja je funkcija parna, a koja je neparna? y = x 3 + 3x + 1 funkcija u tački − x y ( − x ) = ( − x ) 3 + 3 ⋅ ( − x ) + 1 = − x 3 − 3 x + 1 nije ni parna ni neparna. x + − x 2 ( −x)  + −( − x ) x + − x y( − x ) = = = y ( x ) Funkcija je parna. 2 2 x 9. y = ln Inverzna funkcija. 4 y y x = ln  x = 4x = y 4 4 funkcija siječe osu y u broju 4. 1 10. y = 1 − x − 1 y( x ) =

I1 D : x − 1 = 0 9

x =1

x ∈ ( − ∞,1)

1 1 + ( x − 1) 1 y= D : x ∈ R /{ 0} x y=

I2

y

x ∈ [1,+∞ )

x

1 1 − ( x − 1) 1 y= 2− x D: x ≠ 2 y=

x=0

1 D: x ≠3 11. y = x−3 x > 0 funkcija je pozitivna x < 0 funkcija je negativna

y=−

x=1

x=2

1 3

x=3

12. y =

1 2−x

D: x ≠ 2

x > 0 funkcija je negativna x < 0 funkcija je pozitivna 1 x = 0 siječe y – osu u y = 2

y=

1 2

x=2

Granične vrijednosti - ( limesi ) 1 an = - niz n

0

1 4

1 1 3 2

1

(a-ε, a+ε) - epsilon okoline tačke a 10

a-ε

(

a

)

a+ε

ε okoline tačke a

1

=0 lim n→∞ n

a 0 n k + a1n k −1 + ⋅ ⋅ ⋅ + a n ⋅ n 0

lim k k −1 + ⋅⋅⋅ + b n →∞ b n + b n

1 =∞ lim n →0 n

0

1

n

⋅n

0

=

a0 b0

( k ∈ N )( n ≠ 0 ∧ k ≠ 0)

7 6n − 7 6n − 7 / : n n =6=2 = lim = lim 13. lim 3 n →∞ 3n + 2 n→∞ 3n + 2 / : n n →∞ 3 + 2 n n  1  1  1  1  ⋅  n − 1     − 1 1− n  1  1  3 1 1  = 3 =  3 3 14. lim  + 2 + ⋅ ⋅ ⋅ + n  = lim  ⋅ 1 lim lim  2  3 3 2  n →∞ 3 3  n →∞ n →∞  − 1  n →∞  −     3 3      6−

  = 1  2  

15. 2 2n +4 (1 + 2 n ) 1 + 2 + 3 + ⋅ ⋅ ⋅ + 2n 2 n ( 1 + 2 n ) 2 + 4 n n n 2 = = = : = =4 lim lim lim lim n 1 1+ 2 + ⋅⋅⋅ + n n( 1 + n ) 1 + n n lim n →∞ n →∞ n → ∞ n → ∞ n → ∞ (1 + n ) +1 2 n x 2 − 5 12 − 5 4 = =− 16. lim 1+ 2 3 x →1 x + 2

17.

x 2 + 6 x − 16 ( x − 2)( x + 8) = x+8 2+8 = lim = =2 lim lim 2 2+3 x + x−6 x →2 x →2 ( x − 2 )( x + 3) x→2 x + 3

18.

(

)

2  3 ⋅ (1 + x ) − 2 ⋅ 1 + x + x 2 3 + 3x − 2 − 2 x − 2 x 2  3 − = = =   lim lim lim 3 2 1 − x 2  x→1 (1 − x ) ⋅ (1 + x ) ⋅ 1 + x + x 2 x →1  1 − x x →1 (1 − x ) ⋅ (1 + x ) ⋅ 1 + x + x

(

)

(

)

1 + x − 2x ( − 2 x − 1)( x − 1) − ( − 2 x − 1) = lim = lim = 2 2 2 x →1 (1 − x ) ⋅ (1 + x ) ⋅ 1 + x + x x →1 − (1 − x ) ⋅ (1 + x ) ⋅ 1 + x + x x →1 (1 + x ) ⋅ 1 + x + x 2x + 1 2 +1 1 = lim = = 2 2⋅3 2 x →1 (1 + x ) ⋅ 1 + x + x 2

= lim

(

(

)

(

)

)

x2 x = −1 - vertikalna asimptota x +1 y = 0 ⇒ x = 0 nula funkcije je u nuli y 2 x2 y x2 x2 1 : 2 = lim =1 kosa asimptota k = lim = lim x + 1 = lim 2 x x →∞ x x →∞ x →∞ x + x x x →∞ 1 + 1 x 2 2 2  x  x − x −x x −x  = lim n = lim ( y − k ⋅ x ) = lim  − x  = lim  = −1  x + 1  x →∞ x + 1 x →∞ x →∞  x + 1 x →∞   0 -1

19. y =

x y= x+1

11

(

)

x2 − 4 20. y = 2 x −1

y( − x ) =

( − x) 2 − 4 = ( − x) 2 − 1

x2 − 4 = y funkcija je parna x2 −1

x 2 − 4 = 0 ⇒ x1, 2 = ±2 nule funkcije x 2 − 1 = 0 ⇒ x = ±1 vertikalne asimptote x2 − 4 1− 4 − 3 = = =∞ lim 2 1−1 0 x →1 x − 1 x 2 − 4 ( − 1) 2 − 4 − 3 = = =∞ lim 2 ( − 1) 2 − 1 0 x → −1 x − 1

vertikalne asimptote

4 1− 2 x2 − 4 x2 − 4 / : x2 x =1 = lim 2 = lim lim 2 2 1 x →+∞ x − 1 x →+∞ x − 1 / : x x →+∞ 1 − x2

y x =0⇒ y =

0−4 =4 0 −1

(0,4)

y=1 -1 0 1 2 −x x -2 x y( − x ) = = − ( − x ) 2 − 9 x 2 − 9 funkcija je neparna x2 − 9 D : x ≠ ±3 x = 0 nula funkcije

21. y =

12

x

x

0

y = lim 2 = = 0 horizontalna asimptota je x – osa lim 1 x →∞ x →∞ x − 9 x

3

3

= lim = =∞ lim 2 0 x →3 x − 9 x →3 9 − 9

vertikalne asimptote

x −3 −3 = lim = =∞ lim 2 2 0 x → −3 x − 9 x → −3 ( − 3) − 9 y

y=

-4

-3

-2

-1

0

1

2

3

4

x x2 − 9

x

x=3

x=-3

OMM X ~ OAB 5 2 proporcionalnost = ∞; =0 0 ∞ stranica 0 ∞ ∞ 0 ; ; ; ; neodređeni oblici MM X AB 0 ∞ 0 ∞ = B OM X OA 1 1− 3 x 1M− 3 x 1 1 = lim − = −3 =− 22. lim x − 1 = lim 3 3 3 2 2 3 1 + 1 +1 x →1 x →1 − 1 − 3 x x + 3 x + 1 sinxα→1 ABx + 3 x + 1 = ⇒ AB = tgα α cos α 1 4 + x + 2 ⋅  ( 4 + x ) 2 + 3 ( 4 + x ) ⋅ 4 + 3 16  4+ x −2 0 4 +Mxx − 2A(1,0)  = = lim 3 ⋅ lim 3 3 3 2 4+ x − 4 4+ x − 4 x →0 x →0 4 + x + 2 ⋅  ( 4 + x ) + 3 ( 4 + x ) ⋅ 4 + 3 16    23. ( 4 + x − 4) ⋅  ( 4 + x ) 2 + 3 ( 4 + x ) ⋅ 4 + 3 16  3 16 + 3 16 + 3 16 3 ⋅ 23 2 33 2   = lim = POAM= < Pisj.OAM < POAB = 2+2 4 2 ( 4 + x − 4) ⋅ 4 + x + 2 x →0 1 ⋅ sin x x ⋅ 1 1 ⋅ tgx sin x < < /: B 2 2 2 2 M x 1 sin x 1< < = 1 24. lim x sin x cos x x →0 sin x cos x < <1 Mx A Dokaz : 0 x x → 0 ⇒ cos x = 1 sin x 1< <1 x 13 sin x =1 lim x x →0

(

)(

(

( (

)

)

) )

sin ( α + β ) = sin α cos β + cos α sin β sin ( α − β ) = sin α cos β − cos α sin β sin ( α + β ) − sin ( α − β ) = 2 sin α cos β α+β = x α+β = x (+) (-) α −β = y α −β = y 2α = x + y 2β = x − y x+ y x− y α= β= 2 2 sin x − sin y = 2 cos

14

x+ y x− y ⋅ sin 2 2

25.

(

)(

)

sin 4 x − sin 4 a sin 2 x − sin 2 a ⋅ sin 2 x + sin 2 a = lim = lim x−a x−a x→a x→a = lim

( sin x − sin a )( sin x + sin a ) ⋅ (sin 2 x + sin 2 a ) =

x−a x+a x−a 2 ⋅ cos ⋅ sin ⋅ ( sin x + sin a ) ⋅ sin 2 x + sin 2 a 2 2 = lim = x−a x →a x+a x−a cos ⋅ sin ⋅ ( sin x + sin a ) ⋅ sin 2 x + sin 2 a 2 2 = lim = cos a ⋅ 2 sin a ⋅ 2 sin 2 a = 4 ⋅ sin 3 a ⋅ cos a x − a x →a 2 0 ∞ 1∞;0 ∞; ∞0 ; ; Neodređeno 0 ∞ x →a

(

)

(

x

 1 1 +  =  lim x x →∞  ln(1 + x ) =1 lim x x →0

1

(1 + x ) x lim x→0

)

=   ≈ 2,71828

a x −1 = ln a lim x x →0

x − 1 =1 lim x x →0

lim x →0

(1 + x ) a − 1 = a x

26. x

x +1 −2 ⋅ ⋅x x +1

x

− 2  −2  x −1  x +1− 2     = lim   = lim 1 +  lim x + 1 x →∞  x + 1  x →∞  x + 1  x →∞  =

− 2x / : x

= lim lim x →∞ x + 1 / : x x →∞

x + 1 27. lim   x →∞  x 

28.

x2

(1 + sin x ) lim x →0

−2 1 = −2 = − 2 = 2 1  1+ x

 1 = lim 1 +  x x →∞  1 x

=

x⋅ x

= lim x = ∞ = ∞ x →∞

1

1 x x  = lim 1 + sin x ⋅  = lim (1 + x ) x =  sin x  x →0  x →0

29. 1

( cos x ) x lim x →0 =

lim x →0

2

1

= lim (1 + cos x − 1) cos x −1⋅

cos x −1 x2

=

x →0

cos x − 1 − (1 − cos x ) = lim = − lim 2 x x2 x →0 x →0

2 sin 2 x2

x x 1 sin 2 2 =− 2 = − 1 = − 2 = 1 lim 2  x →0 2 ⋅ x ⋅ x 2 2

II. način sin 2

15

x 1 − cos x = 2 2

2 sin 2

x = 1 − cos x 2

cos x = 1 − 2 sin 2

x 2

1

1

2   2 xx 2 x  − 2 sin 2 x 1 − 2 sin = 1 + − 2 sin     2 lim lim 2 2 x →0  x →0 



− 2 sin 2 x2

x 2



=

1 2

1

=



1

 1  x − 1   x − 1 = x ⋅ =1 30. lim   lim 1 x ←∞ x → ∞   x

Odrediti asimptote funkcija : 1 ⇒ x D: x ≠ 0

31. y = x −

lim x →0

2

y=

x −1 = lim x x →0

y = kx + n

x2 −1 x 1 x 2 = 1 = ∞ vertikalna asimptota je x=0 tj. y – osa. 1 ∞ x

1−

1 x2 −1 1− 2 2 x −1 x =1 k = lim x = lim 2 = lim x 1 x x →∞ x →∞ x →∞ 1 −  x2 −1  x2 −1− x2 n = lim  − x  = lim = x =0 x x 1 x →∞   x →∞ y = x kosa asimptota

nule funkcije x 2 − 1 = 0 x2 = 1 x1, 2 = ±1 y y=x

y = x−

1 x

x

x=0 D: x+2≠ 0 x−2 32. y = vertikalna asimptota x = −2 x+2 x ≠ −2 x − 2 = 0 ⇒ x = 2 nula funkcije

16

2 x−2/:x x =1 = lim lim x →∞ x + 2 / : x x →∞ 1 + 2 x 1−

y = 1 horizontalna asimptota

Znak -∞

-2

x-2

-

x+2 f(x)

2

+

0

+

+∞

0

+ +

-

+

y=1 -2

-1

0

1

2

y=

(0,-1)

33. y =

x

x−2 x+2

D : x + 1 ≠ 0 x ≠ −1

( x + 1) 2 x

−1

x

1

= lim 2 = lim = − = ∞ lim 2 0 x →−1 ( x + 1) x → −1 x + 2 x + 1 x → −1 1 − 2 + 1

vertikalna asimptota

1 x 0 x = = = 0 horizontalna asimptota je y = 0 x- osa lim lim 2 1 x →∞ x + 2 x + 1 x →∞ 1 + 2 + 1 x x2 y>0 x>0 znak y < 0 x < 0 y′ =

x 2 + 2 x + 1 − x ⋅ ( 2 x + 2)

y ( 1) =

17

( x + 1)

1

(1 + 1) 2

=

4

=

x 2 + 2x + 1 − 2x 2 − 2x

( x + 1)

4

=

− x2 +1

( x + 1)

4

=

1  1 1,  funkcija ima maksimum u tački T 4  4

(1 + x )(1 − x ) = 1 − x ( x + 1) 4 ( x + 1) 3

y

y=

x

( x +1) 2

1 4 -1

0

1

y=0

x

x=-1

34. y = x − x 2 + x − 2

D : x 2 + x − 2 ≥ 0 ⇒ x ∈ ( − ∞,−2] ∪ [1,+∞ )

2 lim x − x + x − 2 = lim

(x −

)(

x2 + x − 2 ⋅ x + x2 + x − 2

x + x2 + x − 2 2 −1+ −x+2 1 x = lim = lim =− 2 2 1 2 x →∞ x + x + x − 2 x →∞ 1+ 1+ − 2 x x x →∞

x →∞

) = lim x x →∞

2

− x2 − x + 2

x + x2 + x − 2

y = 0 x − x2 + x − 2 = 0 x = x2 + x − 2 /2

x = 2 nula funkcije

x2 = x2 + x − 2

y

y = x − x2 + x − 2 nema funkcije -2

-1

(-2,-2)

18

0

x 1

2

y=−

1 2

=

x2 +1 x2 − 4 D : x2 − 4 ≠ 0

35. y =

x1, 2 ≠ ±2 x ∈ ( − ∞,−2 ) ∪ ( − 2,2) ∪ ( 2,+∞ )

x 2 + 1 = 0 nema nula ( − 2) 2 + 1 = 5 = ∞ x2 +1 = lim lim 2 2 0 x → −2 x − 4 x → −2 ( − 2 ) − 4

vertikalne asimptote x = −2 ∧ x = 2 x2 +1 22 + 1 5 = lim 2 = =∞ lim 2 0 x →2 x − 4 x →2 2 − 4 1 1+ 2 2 x +1 x =1 = lim horizontalna asimptota y = 1 lim 2 x →∞ x − 4 x →∞ 1 − 4 x2 Znak -∞

-2

x2 +1

+

x−2

-

x+2

-

y

(

)

(

0

) = 2x

2x ⋅ x 2 − 4 − 2x ⋅ x 2 + 1

Znak y ′

(x

2

−4

)

2

3

(x

-10x

x 4 − 8 x 2 + 16

19

x2 +1 0 +1 1 = =− 2 4 x −4 0−4

2

+ +

0

+

+

-

+

− 8x − 2x 3 − 2 x

-

x = 0 y( 0) =

+∞

+

+

Prvi izvod funkcije y′ =

2

−4

)

2

-2

− 10 x x 4 − 8 x 2 + 16

=

0

2

+

+

+

-

-

+

+

+

+

+

+

-

-

x−4 2 =y x+1

2

y

y=1 x -2

-1

0

1

2

T

ln x + 2 ln x D : ln x ≠ 0 ⇒ x > 1

x= -2

x=2

36. y =

1 ln x + 2 y = lim = lim x = 1 Horizontalna asimptota y =1 lim ln x x →∞ x →∞ x →∞ 1 x ln x + 2 0 + 2 2 y = lim = = = ∞ Vertikalna asimptota je x=1 lim ln x 0 0 x →1 x →1 1 ln x + 2 y = lim = lim x = 1 lim ln x x →0 x →0 x →0 1 x y = 0 ln x + 2 = 0 ln x = −2 x = − 2 1 x= 2 

Znak funkcije

20

-∞

1

ln x + 2

-

ln x

-

-

y

+

-

0

+∞

+

+

0

+ +

( ,3)

3

y=

ln x + 2 ln x

( 0,1) y=1

1   2 ,0   

1



x

x=1

Naći nule funkcija ? x3 − 8 x3 + 8 D : x3 + 8 ≠ 0

37. y =

( x + 2) ( x 2 − 2 x + 4 ) ≠ 0

x+2≠0 ∧ x ≠ −2

x 2 − 2x + 4 ≠ 0

( x − 2) ( x 2 + 2 x + 4) = 0 x=2

Nula funkcije je x = 2 x 4 − 17 x 2 + 16 x2 + 2 D : x2 + 2 ≠ 0

38. y =

(∀

x ∈ R)

x2 = t t 2 − 17t + 16 = 0

t1 = 1 t 2 = 16

x1, 2 = ±1



39. y = log( x − 1)

x −1 > 0 x >1 D: log( x − 1) = 0 x −1 = 1

21



x2 = 1

x3, 4 = ±4

∧ x 2 = 16 y

y = log( x − 1)

x ∈ (1,+∞ ) x = 2 nula funkcije

x 0

1

2

1 − ln x x2 D: x >0 1 − ln x = 0 ln x = 1

40. y =

y

x ∈ ( 0,+∞ ) x =  nula funkcije y =

1 − ln x x2

y = 1− ln x 41. y = tgx − 3



tgx − 3 = 0 tgx = 3 π x = + kπ nula funkcije 3 y

−π



2π 3

π − 2

0

42. Izračunati

f( x) + f 1 

f  1  = log 6

1 9 + 3 log 3 x x

   x

  x

π π 3 2

π 4π

3

3π 2

x



, ako je dat izraz f ( x ) = log 6 x + 3 log3 9 x ?

f  1  = − log 6 x + 3( log 3 9 − log 3 x )    x

f ( x ) + f  1  = log 6 + 3 log 3 9 x − log 6 x + 3( log 3 9 − log 3 x )   x

f ( x ) + f  1  = 3 ⋅ ( log 3 9 + log 3 x ) + 6 − 3 log 3 x = 6 + 3 log 3 x + 6 − 3 log 3 x = 12   x

43. y = − ln x − 2

− ln x − 2 = 0 ln x = −2 nula funkcije 1 x= 2 

22

x

y = −2 − ln x > 0

 1  x ∈  0, 2    

 1  x ∈  2 ,+∞   

y = −2 − ln x < 0 y

y = − ln x − 2 x 1 2

44. y = sin x

x 0 y 0

π 6 1 2

π 4

1

π 3

2 2

3 2

π 2

π

3π 2



1

0

-1

0

sin ( x + 2kπ ) = sin x k = 0,±1,±2,±3... sin x > 0 , x ∈ ( 0 + 2kπ , π + 2kπ )} k ∈ Z sin x < 0 , x ∈ ( π + 2kπ ,2π + 2kπ )

π  π  x ∈  − + 2kπ , + 2kπ  y ↑1−1 2  2  3π π  x ∈  + 2kπ , + 2kπ  y ↓1−1 2 2  y

1

y=sinx x 0

-1

23

π



45. y = arcsin x

x

0

1 2

arcsin x

0

π 6

D : −1≤ x ≤1

2 2

3 2

π 4

π 3

1

0

-1

0

π 2

π

3π 2



y (0,π)

x -1

0

1 y=arcsinx

1 y=sinx -2π



0 -1 y=arcsinx

24

π



46. y = cos x

1 y=cosx -2π



3π 2





π

0

2

π

3π 2

π

2 -1

x = ( 2k + 1) ⋅

cos x = 0, cos x > 0, cos x < 0,

47. y = arccos x

π 2

,(k ∈ Z )

π  π  x ∈  − + 2kπ , + 2kπ  2  2  3π π  x ∈  + 2kπ , + 2kπ  2 2 

3π 2

x ∈ ( 0, π ) y ↓1−1

π

x ∈ ( π ,2π ) y ↑1−1

2

sin x 48. y = tgx = cos x D:

π 2 sin x = 0 ⇒ x = kπ ( k ∈ Z )

cos x ≠ 0; x ≠ ( 2k + 1) ⋅

tgx = 0

-1

0

1



π 2

y=arccosx



25

3π 2



y



3π 2

−π



π 2

0

y=tgx

π

π 2

3π 2



5π 2

y

3π 2

π

π 2

x

0



π 2

−π



cos x sin x D : sin x ≠ 0 ⇒ x ≠ kπ

3π 2

49. y = ctgx = ctgx = 0

26

cos x = 0 ⇒ x = ( 2k + 1) ⋅

π 2

(k ∈ Z)

x

y

−π



π 2

0

y=ctgx

π

π 2

y = arcctgx



3π 2

x

y

2π 3π 2 π

π 2

0 x −

π 2

−π

2x − 3 x+3 D: x+3≠ 0 x ≠ −3 x = −3 vertikalna asimptota y = 0 2x − 3 = 0 -3 3 Znak funkcije x= 2 0 y +

50. y =

2x − 3 x+3

27

+ + -

0

+ + +

y

y=2 2 x

3 2

51. y = shx =

x − − x 2

D=R y = shx = 0

(sinus hiperbolički x)



x = 0 nula funkcije − x − x x − − x y( − x ) = =− = − y ( x ) funkcija je neparna 2 2 y y=shx x

y

x + − x 52. y = chx = 2 D=R y min ( 0 ) = 1

y=shx

y − x + x x + − x y( − x ) = =− = y ( x ) funkcija je parna 2 2

shx x − − x = 53. y = thx = chx x + − x

x 0

28

x y=1

y=thx y=-1

54. y = cthx =

chx x + − x = shx x − − x

y

y=1 x 0

y=cthx y=-1

Granične vrijednosti funkcije Niz { a n } realnih brojeva ima graničnu vrijednost a ako za proizvoljan ε > 0 postoji prirodan broj n0 takav da je za svaki n > n0 ispunjena apsolutna vrijednost ( a n − n ) ≤ ε označavamo sa

an = a lim n →∞

. Niz koji ima graničnu

vrijednost nazivamo ga konvergetnim, a onaj koji nema vrijednosti nazivamo divergetnim. an =

1 n

0

1 4

1 1 3 2

1

(a-ε, a+ε) - epsilon okoline tačke a

55. a n =

29

5n − 2 n+2

a-ε

(

a

)

a+ε

ε okoline tačke a

an − 5 < ε an − 5 <

ε = 0,1

1 10

5n − 2 1 −5 < n+2 10 5n − 2 − 5n − 10 1 < n+2 10 − 12 1 < n + 2 10 − 120 < n + 2 n > −122 a 0 x n + a1 x n −1 + ⋅ ⋅ ⋅ + a n −1 ⋅ x + a n

lim n n −1 + ⋅⋅⋅ + b n →∞ b x + b x 0

n −1

1

⋅ x + bn

a0 x n + a1 x n −1 + ⋅ ⋅ ⋅ + a n

lim n+ k + bx n + k +1 + ⋅ ⋅ ⋅ + b n →∞ b x 0

lim x →∞ a



m n

58.

59.

60.

30

= 0 ,(k ∈ N )

b0 x n + b1 x n −1 + ⋅ ⋅ ⋅ + bn

=∞

1

=

n

am

6

n + 25n

n + 25n / : n

= lim lim 3 x →∞ 8n18 − 4n + 5 x→∞ 3 8n18 − 4n + 5

2

57.

a0 b0

n

a 0 x n+ k + a1 x n + k −1 + ⋅ ⋅ ⋅ + a n+ k

6

56.

=

x +x

= lim lim 5 x →∞ x − 1 x →∞

lim x → −∞ lim x →∞

1 x

3



=

1 2

=

1 1 2

6

/ : n6

= lim x →∞

1 1 + 4 3 x x = 0 =0 1 1 1− 5 x =

3

1  3

x −1 x −1 / : x = lim 2 = lim 2 x / : x3 x →∞ x x →∞

1 x3 = 1 = ∞ 1 0 x

1−

25 1 1 n5 =3 = 4 5 8 2 8− 5 + 6 n n 1+

3

(

)

2 2 lim x x + 2 − x − 2 = lim x →∞

= lim x →∞

(

x ⋅ x2 + 2 − x2 + 2

)=

x2 + 2 + x2 − 2 4

x⋅

(

4

)

x −1

lim 4 4 x →1 x ⋅ ( x − 1) ⋅ ( x + 1) ⋅ (

61.

x⋅

(

)(

x2 + 2 − x2 − 2 ⋅

x2 + 2 + x2 − 2

x →∞

4x

lim x →∞

)

x +1

( )

x2 + 2 + x2 − 2

x2 + 2 + x2 − 2 = lim x →1

(

x⋅

)(

(

4 4

=

4 =2 2

x

)(

x +1 ⋅

)=

=

)

x +1

)

1 1 = 1⋅ 2 ⋅ 2 4

1− 3 x 3 x − 1 = 3 x − 13 = 3 x − 1 3 x 2 + 3 x + 1 x −1 1− 3 x 1− 3 x 1 1 1 = = lim − =− =− lim lim 3 2 3 2 1+1+1 3 x →1 x − 1 x →1 3 x − 1 x →1 x + 3 x +1 x + 3 x +1

62. y =

(

63.

)(

)

(1 − sin x )(1 + sin x ) cos 2 x 1 − sin 2 x 1 + sin x = limπ 1 − sin 3 x = limπ 1 − sin 3 x = limπ (1 − sin x ) 1 + sin x + sin 2 x = lim 2 x →0 1 + sin x + sin x x→ x→ x→ 2

2

2

(

)

1+1 2 = 1+1+1 3 x x 1 = sin 2 + cos 2 2 2 (-)  x x 2 x 2 x cos x = cos +  = cos − sin 2 2 2 2 x x x x 1 − cos x = sin 2 + cos 2 − cos 2 + sin 2 2 2 2 2 x 1 − cos x = 2 sin 2 2 x 2 sin 2 1 − cos x 2 =2 = lim 64. lim x →0 sin 2 x x →0 sin 2 x 2 2 3 x 65. y = 2 x −1 D : x2 −1 ≠ 0 =

x2 ≠ 1 x1, 2 ≠ ±1 x3 ( − 1) 3 = − 1 = − 1 = ∞ = Funkcija ima vertikalne asimptote lim lim 2 2 1−1 0 x → −1 x − 1 x →−1 ( − 1) − 1 x3 13 1 1 = = = =∞ lim lim 2 2 1−1 0 x →1 x − 1 x →1 1 − 1 x3 1 1 = lim = =∞ lim 2 nema horizontalne asimptote 0 x →∞ x − 1 x →∞ 1 − 1 2 x x 31

k = lim x →∞

x3 x3 1 x2 −1 = = =1 lim 3 x 1 x →∞ x − x

1 3 3  x3   x3  x −x +x 0 n = lim  2 − kx  = lim  2 − x  = lim = lim x = = 0 2 1 x −1 x →∞  x − 1 x →∞ 1 − 1  x →∞  x − 1  x →∞ 2 x 3 y = x Kosa asimptota funkcije y = x . y x2 −1 x 66. y = 3 − x2 D : 3 − x2 ≠ 0 x2 ≠ 3

x

x1, 2 ≠ ± 3

-1 − 3

x

= lim lim 2 x→− 3 3 − x x →− 3

(

3− − 3

x

= lim lim 2 3 − x x→ 3 x→ 3

3

3−

( 3)

2

=

)

2

=

− 3 − 3 = =∞ 3−3 0

x3 y= 2 x −1

3 3 = =∞ 3−3 0

Ima vertikalnu asimptotu, a kose asimptote nema. x

= lim lim 2 x →∞ 3 − x x →∞

1 x

3 −1 x2

=

0 = 0 Horizontalna asimptota je x – osa. −1 y

− 3

0

x

3

x y= 3 − x2 x2 +1 1− x2 D : 1− x2 ≠ 0

67. y =

32

x 2 ≠ 1 x1, 2 ≠ ±1

1

2

2

x +1 / : x = lim / : x2 x →∞

y = lim lim 2 x →∞ x →∞ 1 − x

1 x 2 = 1 = −1 Horizontalna asimptota y=-1. 1 −1 −1 x2

1+

x2 +1 ( − 1) 2 + 1 2 = lim = =∞ lim 2 2 0 x → −1 1 − x x → −1 1 − ( − 1) x2 +1 12 + 1 2 = = =∞ lim lim 2 2 0 x →1 1 − x x →1 1 − 1

Vertikalne asimptote x= -1 i x=1.

Nema nula funkcije. y

x -1

0

1 y= -1

-1 x= -1

x=1

2

x 3− x D: 3− x ≠ 0 x≠3 x2 32 9 = = = ∞ Vertikalna asimptota je x=3 . lim lim 0 x →3 3 − x x →3 3 − 3

68. y =

x2 x2 1 1 k = lim 3 − x = lim = lim = = −1 2 x −1 x →∞ x →∞ 3 x − x x →∞ 3 − 1 x 2 2  x   x  x 2 + 3x − x 2 3x n = lim  − kx  = lim  + x  = lim = lim = −3 3 − x 3 − x 3 − x x →∞  3 − x x → ∞ x → ∞ x → ∞    y = kx + n y y = − x − 3 Kosa asimptota x 0 -3

y = − x− 3

Horizontalne asimptote nema.

y

-3

0 x

-3

0

-3

33

3

3 x − 1 D: x − 1 ≠ 0

69. y =

y

x ≠ 1 x≠0

x ln x D : ln x ≠ 0 x ≠1

x

x=0

70. y =

x>0

y

ovdje funkcije nema

x 1

x=1 y=f(x)

f ( x +∆y )

∆y

B

- priraštaj funkcije def .

∆ y = f ( xračun Diferencijalni + ∆ x ) − f ( x ) f ( ′x ) =

f ( x)

A( x, f ( x ) ) x

34

- priraštaj argumenta x

∆x

x + ∆x

lim ∆x→ 0

f ( x+ ∆x ) − f ( x ) ∆x

∆y =k ∆x k – koeficijent smjera prave (sekant)

tgα =

B

∆y α

α

A( x, f ( x ) )

∆x

x

∆x → 0 B →A s →t

x + ∆x

t

α – ugao između sekante i x- ose

f ( x+ ∆ x ) − f ( x ) f ( ′x ) = lim = k t A( x, f ( x ) ) ∆x ∆ x→ 0

71. f ( x ) = x + 2 f ( x + ∆x ) = x + ∆x + 2 f ( ′x ) = lim ∆x →0

f ( x + ∆x ) − f ( x ) ∆x

= lim ∆x → 0

x + ∆x + 2 − x − 2 ∆x = lim =1 ∆x ∆x →0 ∆x

x′ = 1

( x + C)′ = 1

72. y = C

f( x) = C f ( x + ∆x ) = C

73. f ( x ) = x

35

f ( ′x ) = lim ∆x →0

C −C 0 = lim =0 ∆x ∆x →0 ∆x

y=C

y′ = 0

f ( x + ∆x ) = x + ∆ x x + ∆x − x x + ∆x + x x + ∆x − x ⋅ = lim = ∆x x + ∆x + x ∆x→0 ∆x ⋅ x + ∆x + x ∆x →0 ∆x 1 = lim = x + ∆x + x 2 x ∆x →0 ∆x ⋅ f ( ′x ) = lim

(

(

)

2

x x −1 ( x + ∆x ) 2 f ( x + ∆x ) = ( x + ∆x ) − 1

74. f ( x ) =

( x + ∆x ) 2 − x 2 ( x + ∆x ) − 1 x − 1 =

f ( ′x ) = lim

∆x

∆x →0

= lim ∆x →0

76. 77. 78.

(x lim ∆x →0

2

)

+ 2 x ⋅ ∆x + ∆x 2 ⋅ ( x − 1) − x 2 ( ( x + ∆x ) − 1) ( ( x + ∆x ) − 1) ⋅ ( x − 1) = ∆x

x 3 + 2 x 2 ∆x + ∆x 2 x − x 2 − 2 x∆x − ∆x 2 − x 3 − x 2 ∆x + x 2 = ∆x ⋅ ( ( x + ∆x ) − 1) ⋅ ( x − 1)

(

)

∆x ⋅ x 2 − 2 x + x∆x − ∆x x 2 − 2x = ( x − 1) 2 ∆x →0 ∆x ⋅ ( x + ∆x − 1)( x − 1) ′ 3x 2 + 2 x − 5 = 6 x + 2 ′  x3  1 2 1 1  − x + arctgx  = 3 x − 1 + = x2 −1+ 2  3  3 1+ x 1+ x2   7 3 ′ 7 4 4 7 4 8 ⋅ x = 8 ⋅ x = 8 ⋅ ⋅ x = 14 ⋅ 4 x 3 4 ′ 1 1  2 1 −5 2 1   x − 2 − 5  = 1+ 3 − ⋅ 6 = 1+ 3 + 6 5 x x 5x  x x x 

= lim

75.

)

(

)

(

)

79.

′ 2 1 1 16 + 2+1 ′ 19 ′ 19 −5 ′ 1 3 2 4   3 12 24   24   24  19 24 −1 19 24 19 = x = x = ⋅x = ⋅x = ⋅  x ⋅ x⋅ x  = x ⋅x ⋅x      24 24 24 24 x 5         f ( ′x ) = lim

f ( x + ∆x ) − f ( x ) ∆x

∆x → 0

f ( x + ∆x ) = ( x + ∆ x ) 3

80. f ( x ) = x 3 f ( ′x ) = lim ∆x →0

= lim ∆x → 0

y=x

36

( x + ∆x ) 3 − x 3

(

∆x 2

y ′ = n ⋅ x n −1

( a) − ( b) = ( 3

= lim ∆x →0

∆x ⋅ 3 x + 3x∆x + ∆x ∆x

n

a−b =

Izvod

3

3

3

3

2

)

x 3 + 3 x 2 ∆x + 3 x ⋅ ∆x 2 + ∆x 3 − x 3 = ∆x

) = 3x

a −3 b ⋅

(

3

2

a 2 + 3 ab + 3 b 2

)

81. f ( x ) = 3 x

f ( x + ∆x ) = 3 x + ∆ x

 3 ( x + ∆x ) 2 + 3 ( x + ∆x ) ⋅ x + 3 x 2  x + ∆x − 3 x  = f ( ′x ) = lim ⋅ 2 3 2 ∆ x  3 ∆x →0  ( x + ∆x ) + 3 ( x + ∆x ) ⋅ x + x    x + ∆x − x ∆x = lim = lim = 2 2  3 3 3 ( x + ∆x ) ⋅ x + 3 x 2  3 ( x + ∆x ) ⋅ x + 3 x 2  ∆x →0 ∆x ⋅  ∆ x → 0 ( ) ( ) x + ∆ x + ∆ x ⋅ x + ∆ x +         1 1 1 = lim = lim = 3 3 3 3 2 2 2 2 3 2 ∆x → 0  3 x2  3 ( x + ∆x ) + 3 ( x + ∆x ) ⋅ x + x  ∆x→0 x + x + x   ∆x − 1 82. f ( x ) = x f ( x + ∆x ) = x + ∆x =1 ∆x  x + ∆x −  x x ⋅ ∆x − 1 f ( ′x ) = lim = lim = x ∆ x ∆ x ∆x →0 ∆x → 0 f ( x + ∆x ) = sin ( x + ∆x ) 83. f ( x ) = sin x 3

(

(

)

)

2 cos

x + ∆x + x x + ∆x − x ⋅ sin 2 2 = ∆x

sin ( x + ∆x ) − sin x = lim ∆x ∆x →0 ∆x →0 2 x + ∆x ∆x cos ⋅ sin 2 2 = cos 2 x = cos x = lim ∆x 2 ∆x →0 2 α +β α −β sin α − sin β = 2 cos ⋅ sin 2 2 ′ f ( x ) = sin x f ( x ) = cos x f ( ′x ) = lim

Izvodi složenih funkcija n

u = n⋅u

n −1

( )′ =  u

u

⋅ u′

⋅ u′

( sin u ) ′ = cos u ⋅ u ′

( cos u ) ′ = − sin u ⋅ u ′

( tgu ) ′ =

( arctgu ) ′ =

′ u

u′ cos 2 u

( ln u ) ′ = 1 ⋅ u ′ = u

(

u

)′

84. x 2 − x + 2 = x 2 − x +2 ⋅ ( 2 x − 1) 3 2 85. (tg x − 3tgx + 3x ) = 3tg x ⋅



1

86. (ln ( x − x − 1) )′ = 2 x



1 1 − 3⋅ +3 2 cos x cos 2 x 1

2 x −1 x − x −1

37

u′ 1+ u2

87.

′ 1 −1 ′  sin 2 x  2 1 sin 2 x sin 2 x       ′ ⋅  ⋅     1 − sin 2 x  2  1 − sin 2 x  1 − sin 2 x    ln sin 2 x  =  = =  1 − sin 2 x  sin 2 x sin 2 x  1 − sin 2 x 1 − sin 2 x 1 2

′  sin 2 x  ( sin 2 x ) ′ ⋅ (1 − sin 2 x ) − (1 − sin 2 x ) ′ ⋅ sin 2 x  ⋅   (1 − sin 2 x ) 2  1 − sin 2 x  == = sin 2 x sin 2 x sin 2 x 2 2 ⋅ 1 − sin 2 x 1 − sin 2 x 1 − sin 2 x ( cos 2 x ⋅ 2) ⋅ (1 − sin 2 x ) − ( 0 − 2 cos 2 x ) ⋅ sin 2 x 2 cos 2 x − 2 sin 2 x ⋅ cos 2 x + 2 cos 2 x ⋅ sin 2 x (1 − sin 2 x ) 2 = = = sin 2 x 2 sin 2 x(1 − sin 2 x ) 1 − sin 2 x 2 cos 2 x ctg 2 x = = 2 sin 2 x(1 − sin 2 x ) 1 − sin 2 x ′  u  u ′v − uv ′ ′ ′ ′ ′ ′ ′ ′ ′ (c ⋅ u) = c ⋅ u ( u ± v) = u ± v ( u ⋅ v) = u ⋅ v + u ⋅ v   = v2 v  sin 2 x     1 − sin 2 x   =



88.

[x ⋅ ln(x + 1 + x ) − 1 + x ]′ = (x ⋅ ln(x + 1 + x ) ′ − ( 1 + x )′ = ′     1 =  x ′ ⋅ ln ( x + 1 + x ) + (ln ( x + 1 + x ) ⋅ x  −  ⋅ 2x  =      2 1+ x  ′      2x  ( x + 1+ x ) = =  ln ( x + 1 + x ) + ⋅ x −  2

2

2

2

2

2

2

2

2

    2 1+ x2  

x + 1+ x2

 

)

(

(

)

   x′ + 1 + x 2 x =  ln x + 1 + x 2 + ⋅ x −     1+ x2 x + 1+ x2   

( = ln ( x +

) )

= ln x + 1 + x 2 +

89.

38

1+ x2

1+ x2 + x 1+ x2 x + 1+ x2

⋅x−

x 1+ x2

)

(

1+

2x

 x 2 1+ x2 ⋅ x −  = ln x + 1 + x 2 + =  2 2 x + 1 + x 1 + x 

(

)

= ln x + 1 + x 2 +

x x + 1+ x2



x x + 1+ x2

=

′ ′ ′  2 x a2 x x a x  2 2 2 2      2 a − x + 2 arcsin a  =  2 ⋅ a − x  +  2 arcsin a  =     ′   x   1 +    ′  a2  1 a  = 2 2 2 2   ′  =  x ⋅ a − x + a − x ⋅ x + 2 2  2  x   1 −    a       1  2   a 2  1 x 1 1 a2 − x2 x2 a 2 =  a −x + ⋅ −2 x ⋅   +  ⋅ ⋅ = − + =   2 2 2 2 2 2 2 2 2 a 2  2   2 a −x 2 a −x a −x    x 2 1−     a2 a  

(

( =

a2 − x2

)

2

− x2 + a2

2

2 a −x

 1 90. y = 1 +  

2

)

=

2a 2 − 2 x 2 2

2 a −x

2

=

(

2 a2 − x2 2

2 a −x

)

2

2

= a2 − x2

x

x x

 1  1 ln y = ln1 +  = x ⋅ ln1 +  x x  

′ y′  1    1  ′ = x ⋅ ln1 +  +  ln1 +   ⋅ x y x   x   y′ 1 −1  1 = ln1 +  + ⋅ 2 ⋅x y x  1 x  1 +  x  y′ 1 −1  1 = ln1 +  + ⋅ 1 x y x  1+ x y′ 1  1 = ln1 +  − y x  1  x ⋅ 1 +  x    x   1 1  1  ⋅ 1 +  y ′ = ln1 +  − x x  1    x ⋅ 1 +     x    ln y = x ⋅ ln x ⋅ ( sin x ) 91. y = ( sin x ) x y′ ( sin x ) ′ = ln( sin x ) + x ⋅ cos x = ln ( sin x ) + x ⋅ y sin x sin x

Funkcije

39

A=B ln A = ln B ln x n = n ⋅ ln x

x ⋅ cos x   y ′ = ln ( sin x ) + ⋅ ( sin x ) x  sin x  

92. y = x 3 − 6 x 2 + 9 x − 4 1. Oblast definisanosti D : ∀x ∈ R 2. Parnost funkcije y ( − x ) = ( − x ) 3 − 6 ⋅ ( − x ) 2 + 9( − x ) − 4 = − x 3 − 6 x 2 − 9 x − 4 funkcija niti je parna niti je neparna. 3. Periodičnost funkcije ( ∀ω ≠ 0) funkcija nije periodična y ( x +ω ) ≠ y ( x ) 4. Nule funkcije x3 − 6x 2 + 9x − 4 = 0 x1 = 1

x 3 − 6 x 2 + 9 x − 4 : ( x − 1) = x 2 − 5 x + 4 3

x −x

x 2 − 5x + 4 = 0 x 2 + x3 = 5

2

- 5x 2 + 9x − 4

x 2 ⋅ x3 = 4

- 5x 2 + 5x 4x − 4 4x − 4 ( 0) ( x − 1) ⋅ ( x − 1) ⋅ ( x − 4) = y

x2 = 1 x3 = 4

5. Znak funkcije -∞

1

( x − 1) 2

+

x−4

-

0

-

y

4

+

0

6. Prvi izvod funkcije

(

+∞

y > 0 x ∈ ( 4,+∞ )

+

y < 0 x ∈ ( − ∞ ,1) ∪ (1,4 )

-

0

+

-

0

+

)

y ′ = 3 x 2 − 12 x + 9 = 3 x 2 − 4 x + 3 = 3 ⋅ ( x − 1) ⋅ ( x − 3)

7. Znak prvog izvoda funkcije -∞

3 x −1 x−3

y′ y

8. Grafik funkcije

40

1

+ +

0

3

+∞

+

+

y max (1) = 0

+

+

y min ( 3) = −4

-

-

0

+ +

y

y = x3 − 6x 2 + 9x − 4 x

(1,0) 0

2

1

3

4

-1 -2 -3 -4

93. y = x 3 − 3x + 2 1. Domen D = R = ( − ∞,+∞ ) 2. Parnost y ( − x ) = ( − x ) 3 − 3( − x ) + 2 = − x 3 + 3x + 2 = −( x 3 − 3x − 2) nije ni parna ni neparna. 3. Periodičnost y ( x +ω ) ≠ y ( x )

ω≠0

y ( x +ω ) = ( x + ω ) 3 − 3 ⋅ ( x + ω ) + 2 = x 3 + 3 x 2ω + 3xω 2 + ω 3 − 3 x − 3ω + 2

periodična. 4. Nule x 3 − 3x + 2 = 0 x = 1 pogođena nula

x 3 − 3 x + 2 : ( x − 1) = x 2 + x − 2 x3 − x 2

x2 + x − 2 = 0 x 2 + x 3 = −1

x 2 − 3x + 2

x 2 ⋅ x 3 = −2

x2 − x − 2x + 2 − 2x + 2 ( 0) ( x − 1) ⋅ ( x − 1) ⋅ ( x + 2) = y

x 2 = −2 x3 = 1

-∞

5. Znak( x − 1) 41

x+2 y

2

-2

+

1

+

-

0

-

0

0

+ +

+∞

+ +

0

+

nije

6. Prvi izvod

(

)

y ′ = 3 x 2 − 3 = 3 x 2 − 1 = 3 ⋅ ( x − 1) ⋅ ( x + 1) y′ = 0 x =1 x = −1

7. Znak prvog izvoda -∞

-1

1

+∞

y max ( −1) = 4

x −1

-

x−3

-

+

y′

0

0

+ -

+

y min (1) = 0

+ +

y

8. Grafik

y = x3 − 3x + 2 4

y

3 2 1 x -2

94. y =

-1

0 (1,0)

4x 4 − x2

1.) Domen 4 − x 2 ≠ 0

x ≠ ±2 4 ⋅ ( − x) − 4x  4x  = = −  Neparna funkcija 2.) Parnost y ( − x ) = 2 2 4− x  4 − x2  4 − ( − x)

3.) Periodičnost

42

∀ω ≠ 0

y ( x +ω ) ≠ y ( x )

4.) Nule funkcije y=0

4x = 0 ⇒

x=0

5.) Znak funkcije -∞

-2

-

4x

2− x 2+ x

0

- 0 +

+ + - 0 + + -

y

6.) Prvi izvod

( 4x) ′ ⋅ (4 − x 2 ) − (4 − x 2 ) y′ =



(4 − x )

⋅ 4x

2 2

=

(

4x

4 ⋅ ( − 2)

4x

4 ⋅ ( 2)

4x

4 x

= lim lim 2 2 x → −2 4 − x x → −2 4 − ( − 2 ) = lim lim 2 2 x →2 4 − x x → −2 4 − ( 2 )

4 −1 x2

=

=

=

+∞

+

+ 0 + +

)

+ -

4 ⋅ 4 − x 2 + 2x ⋅ 4x

Funkcija uvijek raste y ↑ ( ∀x ∈ D ) 7) Asimptote

= lim lim 2 x →∞ 4 − x x →∞

2

(4 − x )

2 2

=

16 − 4 x 2 + 8 x 2

(4 − x )

2 2

=

4 x 2 + 16

(4 − x )

2 2

−8 =∞ 0

8 =∞ 0

vertikalne asimptote su x= -2 i x= 2.

0 = 0 horizontalna asimptota je y =0. −1 y

Kose asimptote nema. 8) Grafik

y=

4x 4 − x2 x

-2

x= -2 43

> 0 ∀x

-1

0

1

2

x=2

y=0

95. y =

x3

2( x + 1) 2

1.) Domen D : 2( x + 1) 2 ≠ 0

( − x) 3

2.) Parnost y ( − x ) =

2( − x + 1) 2 3.) Periodičnost y ( x +ω ) ≠ y( x )

x ∈ ( − ∞,−1) ∪ ( − 1,+∞ )

x ≠ −1 =

− x3

2( x − 1) 2 ∀ω ≠ 0

funkcija nije ni parna ni neparna.

4.) Nule funkcije x3 = 0

y=0

5.) Znak funkcije



-∞

x=0 -1

x3

0

-

2( x + 1)

2

+

0

-

y

( x ) ⋅ (2 ⋅ ( x + 1) ) − (2 ⋅ ( x + 1) ) y′ = ′

2

2

-

+

y′ = y′ = y′ =

6 x ( x + 1) − ( 2 ⋅ ( 2 x + 2) ) ⋅ x

(2( x + 1) )

2 2

6 x 4 + 12 x 3 + 6 x 2 − 4 x 4 − 4 x 3

(2( x + 1) )

2 2

3

(

)

(

)

2

(

(

) (

2

)

4

6x x + 2x + 1 − 4x + 4x

= =

(2( x + 1) )

2 2

2 x 4 + 8x 3 + 6 x 2

)

4( x + 1)

4

=

3

)

(

)

2x 2 ⋅ x 2 + 4x + 3 4( x + 1)

4

x 2 ⋅ x 2 + 4x + 3 2( x + 1) 4

y′ = 0

x2 = 0 x1 = 0

x 2 + 4x + 3 = 0 x 2 + x 3 = −4



x 2 ⋅ x3 = 3

( x + 3) ⋅ ( x + 1)

-∞

7.) Znak prvog izvoda

-3

-1

0

+∞

x2

+

+ 0 +

+

x+1 x+3

- 0 + - 0 + + + + 0 +

+ + +

+

+

y′ y

44

3

(

′  3 x 2 ⋅ 2( x + 1) 2 − x 3 ⋅  2 x 2 + 2 x + 1  ⋅x   = 2 2 2 ⋅ ( x + 1)



2 2

2

+ +

(2 ⋅ ( x + 1) )

2

0

+

6.) Prvi izvod funkcije 3

+∞

-

+

y max ( −3) = −

27 8

8.) Asimptote

( − 1) 3 = lim lim 2 2 x →−1 2 ⋅ ( x + 1) x → −1 2 ⋅ ( − 1 + 1) x3

x3

=

−1 = ∞ vertikalna asimptota x= -1. 0

1 1 = =∞ 4 2 nema horizontalne asimptote. 0 + 2 + 3 x x x

= lim lim 2 x →∞ 2 ⋅ ( x + 1) x →∞ 2 x3

x3 1 1 2 ⋅ ( x + 1) 2 k = lim = lim 3 = lim = 2 x 2 x →∞ x →∞ 2 x + 4 x + 2 x x →∞ 2 + 4 + 2 2 x x 3 3 3 2   x − x − 2x − 2x  x 1  − 2 x2 + x −1    n = lim  − x  = lim  = = −1 2 2  = lim 2  x →∞  1 2 ⋅ ( x + 1) 2 x →∞  2 ⋅ ( x + 1)  x→∞ 2( x + 1) y = kx + n

(

x3 1 y = x − 1 kosa asimptota funkcije y = . 2 2( x + 1) 2

x

2

0

y

0

-1

9.) Grafik y

y=

-3

-2

-1

0 -1

27    − 3,−  8  

-2 -3 -4

x= -1

45

1

2

)

x3

2 ⋅ ( x +1) 2

x

96. y = x ⋅ − x D : ( − ∞,+∞ ) 1.) Domen ∀x ∈ R 2.) Parnost y ( − x ) = ( − x ) ⋅ −( − x ) = − x ⋅ x funkcija nije ni parna ni neparna. 3.) Periodičnost Nije periodična 4.) Nule funkcije y=0

x=0

5.) Znak funkcije

-∞

0

+∞

x

-

x

+

+

y

-

+

0

+

6.) Prvi izvod funkcije

′ x x x  x  1 ⋅  −  ⋅ x  ⋅ (1 − x ) 1 − x y′ =  x  = = = x 2 x 2 x    y′ = 0 ⇒ 1− x = 0 x =1

7.) Znak prvog izvoda -∞

1

1− x

+

x

+

y′

0

+∞

-

y max (1) =

+

+

0

-

y

8.) Asimptote x

= lim lim x x →∞  x →∞

9.) Grafik

x′

( ) x



= lim x ←∞

1 1 = = 0 horizontalna asimptota y = 0. x ∞  y

x 0

1

2

−x

y = x⋅ 46

1 

97. y =

ln x x

1.) Domen D : x > 0 ∧ x ≠ 0 2.) Parnost Funkcija u ( − x ) uopšte nije definisana, nije parna ni neparna. 3.) Periodičnost Nije periodična. 4.) Nule funkcije y=0

ln x = 0 ⇒ x = 1

5.) Znak funkcije

0

1

+∞

ln x

-

x

+

+

y

-

+

0

+

6.) Prvi izvod funkcije 1 ⋅ x − 1 ⋅ ln x 1 − ln x x y′ = = 2 x x2 y′ = 0 1 − ln x = 0 ln x = 1 ⇒

x=

7.) Znak prvog izvoda 0

1− ln x

+∞

+

0

+

y′

-

y max ( ) =

+

+

0

1 

-

y

8.) Asimptote 1 ln x 1 = lim x = lim = 0 horizontalna asimptota je x – osa. lim x →∞ x x →∞ 1 x →∞ x

9.) Grafik

y

ovdje funkcija nema vrijednosti 47

0

1

2

ln x y= x

x

98. y =

x 2 + 3x x+4

x+4≠0

1.) Domen D : 2.) Parnost y( − x )

( − x) 2 + 3 ⋅ ( − x) =

=

−x+4

3.) Periodičnost y ( x +ω ) ≠ y ( x )

x ∈ ( − ∞,−4 ) ∪ ( − 4,+∞ )

x ≠ −4

 − x 2 + 3x  x 2 − 3x  nije parna ni neparna. = −  −x+4 x − 4  

∀ω ≠ 0

4.) Nule funkcije

x 2 + 3x = 0 x( x + 3) = 0 x = 0 ∧ x = −3

5.) Znak funkcije -∞

x

-4

-

-3

0

+∞

- 0 -

x+3 x+ 4

- 0 + - 0 + + y + 6.) Prvi izvod funkcije y′ = y′ =

y > 0 x ∈ ( − 4,− 3) ∪ ( 0,+∞ )

+

y < 0 x ∈ ( − ∞ ,− 4) ∪ ( − 3,0 )

+ + +

( 2 x + 3) ⋅ ( x + 4) − 1 ⋅ ( x 2 + 3x ) = 2 x 2 + 3x + 8 x + 12 − x 2 − 3x ( x + 4) 2 ( x + 4) 2 x 2 + 8 x + 12

( x + 4) 2

7.) Znak prvog izvoda y′ = 0 x1 = −2

x 2 + 8 x + 12 = 0 x 2 = −6

-∞

x+2

( x + 4) 2

x+6 y′

-6

+ +

0 0

-2

+ + -

0

+∞

+ + + +

y max ( −6 ) = −6 y min ( −2 ) = −1

y

8.) Asimptote

x 2 + 3x ( − 4 ) 2 + 3 ⋅ ( − 4 ) 16 − 12 4 = lim = = = ∞ vertikalna asimptota x=- 4. lim −4+4 0 0 x → −4 x + 4 x → −4

k = lim x →∞

48

x 2 + 3x 3 1+ 2 x + 3x x+4 = x = 1 =1 = lim lim 2 x 1 x →∞ x + 4 x x →∞ 1 + 4 x

 x 2 + 3x   x 2 + 3x − x 2 − 4 x  −x −1  = lim n = lim  − x  = lim  = = −1  x+4 x →∞  x + 4  x →∞   x →∞ x + 4 1 y = x − 1 kosa asimptota x

1

0

y

0

-1

9.) Grafik y

y=x-1

-6

-5 -4

-3

-2

-1

( − 2,−1)

0

1 -1 -2 -3 -4 -5 -6 -7

( − 6,−9)

-8 -9

x= -4

49

2

3

4

5

6

x

1

99. y = x ⋅  x 1.) Domen D : 2.) Parnost

x≠0 −

y( − x ) = ( − x ) ⋅ 

1 x

=

3.) Periodičnost

−x 1 x

( ∀ω ≠ 0) nije periodična.

y ( x +ω ) ≠ y ( x )

4.) Nule funkcije 1 x ⋅ x

y=0 ⇒

x = 0 nije iz domena i funkcija nema nula.

=0

5.) Znak funkcije y=

1 x ⋅ x

>0

za

x>0

y=

1 x ⋅ x

<0

za

x<0

6.) Prvi izvod funkcije y′ =

1 ′ x ⋅ x

1 ′ 1 1 1 1 1 1 ′  1 −1 x 1  1 x x x x x x   + x⋅  = 1⋅  + x ⋅  ⋅   =  + x ⋅  ⋅ 2 =  − =  x ⋅ 1 −    x x x  x  

7.) Znak prvog izvoda y′ = 0 x = 1 y min (1) = 

-∞

0

x− 1

1 x

x

y′

1

+∞

+

+

0

+ +

-

+

+

+

-

+

y min ( 1) = 

y

8.) Asimptote 1

1

(

)

1

)

1

x  x ⋅ − 1 ⋅ x −2 1 1 x = y = = =  = =0 lim lim lim lim lim −2 1 − − 1 − − − ∞ − − 1 x x →0 x →0 x →0 x →0 x →0  x x

(

y = lim lim x →0 x →0 +

+

1 x

1 x

= lim x →0 +

1 x

(

1

⋅ − 1 ⋅ x −2 = lim  x = 0 = ∞ = +∞ −2 − 1⋅ x x →0 +

vertikalne asimptota x=0.

50

(

)

)

k = lim

1 x ⋅ x

x

x →∞

= lim

1 x

= 0 = 1

x →∞

′  1    x − 1 1 1 1      1  x  −1  x ⋅ − 1 ⋅ x −2  = n = lim  x ⋅  x − x  = lim x ⋅   x − 1 = lim = lim  = lim −2 ′   x →∞   x →∞ 1 − 1 ⋅ x x →∞  x → ∞ x → ∞ 1        x x

(

=

1 x

= 0 = 1

y = x + 1 kosa asimptota funkcije y=

1 x ⋅ x

.

x

-1

y

0

0 1

9.) Grafik y



(1, ) y=

1 x ⋅ x

1 -3

-2

-1

0 -1

1

2

x

-2 -3

100. y = (3 − x 2 ) ⋅ x 1.) Domen D : 2.) Parnost

(

( ∀x ∈ R ) .

)

(

)

 1  y ( − x ) = 3 − ( − x ) 2 ⋅ − x = 3 − x 2  x  funkcija nije ni parna ni neparna.  

3.) Periodičnost. Funkcija nije periodična. 4.) Nule funkcije -∞ y=0

3 − x2 = 0

5.) Znak funkcije 51

x1, 2 = ± 3

3− x 

+ +

3+x

-

y

+

x

+ + 0

+∞

0

+

+

+

-

+

(

)

)

6.) Prvi izvod funkcije

(

)

(

)

y ′ = −2 x ⋅  x + 3 − x 2 ⋅  x =  x ⋅ − x 2 − 2 x + 3 y′ = 0 x1 = −3

− x 2 − 2x + 3 = 0 ∧ x2 = 1

7.) Znak prvog izvoda

-∞

-3

x+ 3

+

x

1− x y′

1

0

+∞

+ +

+

+

-

+

+ + 0

-

y

8.) Grafik y 5,4

(1,2)

( )

2 x

5

y = 3− x ⋅ 

4 3 2 1 -3

-2 - -1 −6   − 3, 3    

0 -2 -3 -4

2 101. y = ln x − 1

52

x 1

2

3

4

−6 3 y max (1) = 2 y min ( −3) =

1.) Domen D : x 2 − 1 > 0 x ∈ ( − ∞,−1) ∪ (1,+∞ ) . 2 2 2.) Parnost y ( − x ) = ln ( − x ) − 1 = ln x − 1 = y ( x ) Funkcija je parna.

3.) Periodičnost. Funkcija nije periodična. 4.) Nule funkcije x2 −1 = 1

y=0

x2 = 2

5.) Znak funkcije

-∞

x −1 x+1

x− 2

-

-

-1

1

-

+∞

+

- 0 + +

y

x1, 2 = ± 2

+

+ + - 0 + + +

-

-

+

6.) Prvi izvod funkcije y′ =

1 2x ⋅ 2x = 2 x −1 x −1 2

7.) Znak prvog izvoda y′ < 0

x < 0,

y↓

y′ > 0

x > 0,

y↑

8.) Grafik y

y = ln x 2 − 1 -2 - -1

53

0

12

x

x 2 − 2x + 1 x2 +1 1.) Domen D : ( ∀x ∈ R ) .

102. y =

2.) Parnost y ( − x )

( − x ) 2 − 2( − x ) + 1 x 2 + 2 x + 1 = = nije ni parna ni neparna. x2 +1 ( − x) 2

3.) Periodičnost.Nije periodična. 4.) Nule funkcije x 2 − 2x + 1 =0 x2 +1

y=0

( x − 1) 2 = 0

5.) Znak funkcije

0

1

( x − 1) 2

+

6.) Prvi izvod funkcije

0

+

x2 +1

y′ =

x1, 2 = 1 dvostruka nula.

+ +

+

y

+∞

0

+

( 2 x − 2) ⋅ ( x 2 + 1) − 2 x ⋅ ( x 2 − 2 x + 1) = 2 x 3 + 2 x − 2 x 2 − 2 − 2 x 3 + 4 x 2 − 2 x

( x + 1) 2 x − 2 2 ⋅ ( x − 1) 2 ⋅ ( x + 1) ⋅ ( x − 1) y′ = = = ( x + 1) ( x + 1) ( x + 1) 2

2

(x

2

2

2

)

+1

2

2

2

2

2

2

2

7.) Znak prvog izvoda

-∞

x− 1

-

x+1

( x y+′ 1) 2

-1

2

0

1

+

0

+ +

+

+

+

+

-

+

y min (1) = 0 y max ( −1) = 2

y

8.) Asimptote

lim x →∞

2

2

x − 2x + 1 / : x = lim x2 +1 / : x2 x →∞

2 1 + x x2 1 = = 1 horizontalna asimptota y=1. 1 1 1+ 2 x

1−

Kose i vertikalne asimptote ova funkcija nema.

54

9.) Grafik y

5 4

( − 1,2)

x 2 − 2 x +1 y= x 2 +1

3 2

(1,0)

1 -3

-2

-1

0

1

x 2

3

y=1

4

-2 -3 -4

103. y =

3

x +1 x2

1.) Domen D : x ≠ 0 .

( − x) 3 + 1 = − x3 + 1 nije ni parna ni neparna. x2 ( − x) 2

2.) Parnost y ( − x ) =

3.) Periodičnost. Nije periodična. 4.) Nule funkcije y=0 x = −1

x3 + 1 = 0

( x + 1) ( x 2 − x + 1) = 0

5.) Znak funkcije

-∞

x +1

+ + -

2

x − x +1 2

x

y

6.) Prvi izvod funkcije

(

-1

)

0

0

+ + + +

(

0

)

3 x 2 ⋅ x 2 − 2 x ⋅ x 3 + 1 3x 4 − 2 x 4 − 2 x x ⋅ x 3 − 2 x3 − 2 = = = x4 x4 x4 x3 y′ = 0 x3 − 2 = 0 x3 = 2 x=3 2 y′ =

(

)(

x 3 − 3 23 = x − 3 2 x 2 + x ⋅ 3 2 + 3 4

55

)

+∞

+ + + +

7.) Znak prvog izvoda -∞

0

x−3 2

+∞

+ +

x3 y′

0

+ + -

0

y min ( 3 2 ) =

+ + + +

3 3

y

8.) Asimptote k = lim x →∞

x3 + 1 1 1+ 3 3 2 x +1 x x = 1 =1 = lim 3 = lim x 1 1 x x →∞ x →∞

x3 + 1 x3 + 1 − x3 1 1 − x = = lim 2 = = 0 lim 2 2 ∞ x x x →∞ x →∞ x →∞ x y = kx + n y = x kosa asimptota.

n = lim

Horizontalne asimptote nema. x3 + 1 = lim lim x2 x →0 x →∞

9.) Grafik

1 x3 = 1 = 0 vertikalna asimptota je y – osa. 1 ∞ x y

1+

3  3  2, 3  4 

x3 + 1 y= 2 x

1 -3

-2

-1

0 -1 -2

y=x

56

-3

1

2

x

4

≈2

104. y =

2x − 1

( x − 1) 2

1.) Domen D : x − 1 ≠ 0

x ≠1 2 ⋅ ( − x ) − 1 − ( 2 x + 1) = 2.) Parnost y ( − x ) = ( − x − 1) 2 ( x + 1) 2 nije ni parna ni neparna funkcija.

3.) Periodičnost. Nije periodična. 4.) Nule funkcije y=0



2x −1 = 0

x=

1 2

5.) Znak funkcije -∞

1

2x − 1 ( x − 1) 2

-

y

0

+∞

+

+

+

-

+

+ 0

+ +

6.) Prvi izvod funkcije y′ =

2( x − 1) 2 − 2( x − 1) ⋅ ( 2 x − 1)

( x − 1) 4 2 x ⋅ (1 − x ) y′ = ( x − 1) 4

7.) Znak prvog izvoda

( x − 1) 4

x=0

-∞

0

2x

+

1− x y′ 2x − 1

2x 2 − 4x + 2 − 4x 2 + 2x + 4x − 2

y′ = 0

( x − 1) 4

8.) Asimptote

=

0



x = 1∉ D 1

+∞

+ +

0

+ +

+

+

0

-

-

+

y min ( 0 ) = − 1

-

y 2 −1

1 = +∞ − − 0+ 2x − 1 2 −1 1 = lim = + = +∞ vertikalna asimptota x = 1. lim 2 2 0 x →1+ ( x − 1) x →1+ (1 − 1) 2 1 − 2x − 1 2x − 1 0 x x2 = lim 2 = lim = = 0 horizontalna asimptota. lim 2 1 x →∞ ( x − 1) x →∞ x − 2 x + 1 x →∞ 1 − 2 + 1 x x2 = lim lim 2 2 x →1 ( x − 1) x →1 (1 − 1)

=

Kose asimptote ova funkcija nema. 57

9.) Grafik

y

y=

2x −1

( x − 1) 2

1 2 -3

-2

-1

1

0

( 0,−1)

2

x

-1 -2 -3 x= 1

-4

105.

( x − 2) 3 y= x2 +1

x ∈ ( − ∞,+∞ )

1.) Domen D := R

( − x − 2) 3 − ( x + 2) 3 = = funkcije nije ni parna ni neparna. x2 +1 ( − x) 2 + 1

2.) Parnost y ( − x )

3.) Periodičnost. Nije periodična. 4.) Nule funkcije y=0

x−2=0

x=2 -∞

5.) Znak funkcije

( x − 2) 2 x− 2 6.) Prvi izvod funkcije y′ =

(

)

x2 +1 y

3( x − 2 ) 2 ⋅ x 2 + 1 − 2 x ⋅ ( x − 2) 3

y′ = 0

(x

2

)

+1

x-2 = 0 x1 = 2

2

y′ =

58

x 3 = −3

( x − 2) 2 ⋅ ( x + 3) ⋅ ( x + 1)

(x

2

)

+1

2

+ + -

+∞

0 0

+ + + +

0

( x − 2) 2 [3 x 2 + 3 − 2 x 2 + 4 x ] ( x − 2 ) 2 ( x 2 + 4 x + 3) = =

x 2 + 4x + 3 = 0 x 2 + x 3 = −4 x 2 ⋅ x3 = 3

x 2 = −1

2

(x

2

)

+1

2

(x

2

)

+1

2

7.) Znak prvog izvoda -∞

( x − 2) 2 ( x + 1)

+

-1

+

2

+

0

+∞

+

y max ( −3) =

2

2

x+3 y′

8.) Asimptote

-3

- 0 + - 0 + 0 - 0

+ + + + + + + 0 +

y min ( −1)

( − 5) 3 10

( − 3) 3 = 2

=

− 125 10

=

− 27 2

y prev ( 2 ) = 0

y

( x − 2) 3

3

 2 1 −  3 3 2 ( x − 2) / : x 1 x x + 1 k = lim = lim 3 = lim  = =1 3 x 1 x →∞ x →∞ x + x / : x x →∞ 1 + 1 2 x 3  ( x − 2)   x 3 − 6 x 2 + 12 x − 8 − x 3 − x  − 6 x 2 + 11x − 8  = lim n = lim  2 − x  = lim  =  x2 +1 x2 +1  x +1 x →∞   x →∞  x→∞  11 8 −6+ − 2 −6 x x = lim = = −6 1 1 x →∞ 1+ 2 x ( x − 2) 3 y = x − 6 kosa asimptota funkcije y = . -1 0 6 1 x2 +1 x

Funkcija presijeca kosu asimptotu. y = x−6

( x − 2) 3 y= x2 +1



( x − 2) 3 − x − 6 = 0

( x − 2) 3 x2 +1

= x−6

x2 +1 x 3 − 6 x 2 + 12 x − 8 − x 3 − x + 6 x 2 + 6 =0 x2 +1 11x − 2 =0 x2 +1 11x − 2 = 0 2 1 x= ≈ 11 5

59

y

-7

-6

0

-5

9.) Grafik y

3 ( x − 2) y=

x2 + 1

( 2,0) -6

-5 -4

-3

-2

-1

0

( − 2,−1)

1 -1 -2 -3 -4 -5 -6 -7

( 0,−8)

-8 -9 -10

− 25    − 3,  2  

-11

-12 -12,5 -13 27  -13,5   − 1,−  2  

106. y = ( x − 1) ⋅ ln 2 ( x − 1) 1.) Domen D : x − 1 > 0 x > 1 x ∈ (1,+∞ ) 2.) Parnost. Nije ni parna ni neparna. 3.) Periodičnost. Nije periodična. 4.) Nule funkcije y = 0 x −1 = 1

60

x=2

2

3

4

5

6 y=x-6

x

5.) Znak funkcije

( ∀x ∈ D )

y>0

6.) Prvi izvod funkcije 2 ⋅ ln ( x − 1) x −1 y ′ = ln ( x − 1) ⋅ [ ln ( x − 1) + 2] y′ = 0 ln  ( x − 1) = 0 ln ( x − 1) + 2 = 0 y ′ = 1 ⋅ ln 2 ( x − 1) + ( x − 1) ⋅

x − 1 = 0

ln  ( x − 1) = −2

x −1 = 1

x - 1 = − 2 x = 1 + −2 1 x = 1+ 2 

x=2

ln ( x − 1)

1

21ln+−x()

7.) Znak prvog izvoda

y′ 8.) Asimptote

= lim x →1+

+

2⋅

-

+∞

-

-

0

+

+

0

-

0

y

+

 1  max  1+ 2    

+ 0

+

y

( x − 1) ⋅ ln 2 ( x − 1) = lim lim x →1 x →1 +

2

x −1 ln ( x − 1) = lim = lim 1 1 x →1+ x →1+ 2 ( x − 1) ln ( x − 1) 2

2 ln ( x − 1) ⋅ − 1⋅

1

1 x −1 =

( x − 1) 2

1 x −1 = 2( x − 1) = 0 + lim 1 x →1+

( x − 1) 2

Vertikalna asimptota funkcije je x= 1. 9.) Grafik

y

5

y = ( x − 1) ⋅ ln 2 ( x − 1)

4 3

 1 4  1+ 2 , 2  ( 1,0)  (2,0) 

2 1 0

61

1

2

3

x 4

=

1 ⋅4 2

107. y = ln

x−3 x+2

x−3 >0 x+2 D : x ∈ ( − ∞,−2 ) ∪ ( 3,+∞ )

1.) Domen ln x > 0

x+2<0

x < −2 x > 3

2.) Parnost. Nije ni parna ni neparna. 3.) Periodičnost. Nije periodična. 4.) Nule funkcije x−3 =1 x+2

⇒ x − 3 = x + 2 0 = 5 funkcija nema nula.

5.) Znak funkcije y>0 y<0

za x < −2 za x > 3

6.) Prvi izvod funkcije

′ ′   x − 3  1  x−3 x + 2 1 ⋅ ( x + 2) − 1 ⋅ ( x − 3) x+2− x+3 y ′ = ln ⋅ ⋅ =  =  = 2 x−3  x+ 2 x−3 ( x − 3) ⋅ ( x + 2) ( x + 2)   x + 2  x+2 5 y′ = ( x − 3) ⋅ ( x + 2) y ′ > 0 ⇒ y raste ( ∀x ∈ D )

7.) Asimptote

x−3

−5 = ln + ∞ = +∞ 0 lim x → −2 x−3 0 ln = lim ln = ln 0 = −∞ lim x + 2 x→3 5 x →3 Vertikalne asimptote su x= -2 i x=3. ln = ln lim x + 2 lim x → −2 x → −2

x−3 x−3 /: x ln = lim ln = ln lim x + 2 x→∞ x + 2 / : x lim x →∞ x →∞

je y=0 , odnosno x- osa. 8.) Grafik

y = ln

3 x = ln 1 = 0 horizontalna asimptota 2 1+ x 1−

y

x−3 x+2

x y=0

62

-2

0

3

108. y = x ⋅ ln 2 x 1.) Domen D : x > 0 x ∈ ( 0,+∞ ) . 2.) Parnost y ( − x ) nije definisano. 3.) Periodičnost. Nije periodična. 4.) Nule funkcije y = 0 ⇒ x = 0 ∉ D ln 2 x = 0 ⇒ x = 1

5.) Znak funkcije

0

1

x

+

ln 2 x

+

0

6.) Prvi izvod funkcije

(

+ +

+

y

+∞

0

+

)

′ 1 y ′ = x ′ ⋅ ln 2 x + x ⋅ ln 2 x = ln 2 x + x ⋅ 2 ln x ⋅ = ln 2 x + 2 ln x = ln x ⋅ ( ln x + 2 ) x y ′ = 0 ln x = 0 ln x + 2 = 0 x =1 ln  x = −2 x = − 2 1 1 x= 2 ≈ 8 

7.) Znak prvog izvoda 0

ln x

ln x + 2 y′

1

+

=

1 1 ⋅ 4 ≈ 2 2

+

y

+

+

y min (1) = 1 ⋅ ln 2 1 = 0

-

+

0

+∞

0

 1  max  2   

y

8.) Asimptote 1 1 2 ln x ⋅ 2⋅ 2 ln x 2 ln x 2x 2 2 x = x = x ⋅ ln x = = = =0 lim lim lim lim lim lim −2 1 1 x x →0 x →0 x →0 1 ⋅ − x x →0 − x x→0 x →0 x x2 x2

(

63

)

9.) Grafik

y

5 4 3 2 1

y = x ⋅ ln 2 x

 1 4  2, 2   ( 1,0)  0

1

x 2

3

4

x=0 2

109. y = sin x − sin x 1.) Domen D : R x ∈ ( − ∞,+∞ ) . 2.) Parnost y ( − x ) = ( sin ( − x ) ) 2 − sin ( − x ) = ( − sin x ) 2 + sin x = sin 2 x + sin x Nije parna ni neparna funkcija. y ( x + 2 kπ ) = ( sin ( x + 2kπ ) ) 2 − sin ( x + 2kπ ) = sin 2 x − sin x 3.) Periodičnost Periodična, sa periodom 2kπ . 4.) Nule funkcije sin 2 x − sin x = 0 sin x ⋅ ( sin x − 1) = 0

sin x = 0



x = kπ

sin x = 1 π x = + 2kπ 2

5.) Znak funkcije

y = sin x ⋅ ( sin x − 1)

0

sin x sin x − 1 y

+ - 0 - 0

+ -

0 0

+

6.) Prvi izvod funkcije

y ′ = 2 sin x ⋅ cos x − cos x = cos x( 2 sin x − 1) 0 y′ = 0 cos x = 0 2 sin x − 1 = 0 π Ekstremi : x1 = π + 2kπ x 2 = +cos 2kxπ 2 6 2 + 1 1 1 1 1 5 y π  =   − = − = − min   - Z0) 2 4 2 4x3 = 2πsin+ x2k−π1 ( k ∈ 2 6 6 y π  = 1−1 = 0 y′

- 0

max   2

2 7.) Znak prvog 1 1  1  izvoda

y

64

y

 5π  min    6 

 3π  max    2 

=  − =− 2 4 2 = ( − 1) 2 − ( − 1) = 1 + 1 = 2

y

+ 0 + + 0 + 0 -

0

-

+ -

+

-

-

8.) Grafik y

2

y = sin x − sin x

 3π   ,2   2 

2

− 2π



3π 2

−π

π − 2

0

π   ,0  2 

π

π

 π 1 2  ,−   6 4

 5π 1   ,−  4  6

110. y = cos 2 x + cos x 1.) Domen D : R x ∈ ( − ∞,+∞ ) . 2.) Parnost y ( − x ) = ( cos( − x ) ) 2 + cos( − x ) = cos 2 x + cos x = y ( x ) .

3π 2



3.) Periodičnost. y ( x + 2kπ ) = cos 2 ( x + 2kπ ) + cos( x + 2kπ ) = cos 2 x + cos x = y ( x ) Funkcija je periodična sa periodom 2kπ k = 0,±1,±2... 4.) Nule funkcije y = cos x( cos x + 1) = 0 cos x = 0 π x = ( 2k + 1) ⋅ , 2 (k ∈ Z)

cos x = −1 x = π + 2kπ

0

5.) Znak funkcije

cos x cos x + 1

65

y

+ 0 + + 0 + 0

- 0 +

- 0 -

0

+ + +

x

6.) Prvi izvod funkcije

y ′ = 2 cos x( − sin x ) + ( − sin x ) ⋅ 1 y ′ = − sin x( 2 cos x + 1) y′ = 0 sin x = 0 2 cos x + 1 = 0 x1 = kπ 2cosx = −1 cosx = −

1 2

2π + 2kπ 3 4π x3 = + 2kπ 3 x2 =

7.) Znak prvog izvoda

0

Ekstremi : 2

y

 2π  min    3 

1 1 1 1 1 =  − = − =− 2 4 2 4 2

− sin x

0 - 0 + 2 cos x + 1 + 0 - 0 y′

y max ( π ) = 1 − 1 = 0 2

y

 4π  min    3 

- 0 + 0 -

0

+ + +

y

1 1 1 =  − =− 2 4 2

y max ( 2π ) = ( − 1) 2 − ( − 1) = 1 + 1 = 2

8.) Grafik

y = cos 2 x + cos x

y

( 2π ,2)

( 0,2)

− 111. y = 66

3π 2

sin x 2 + cos x

−π

π   ,0  2 



π 2

0

π

3π  4π 1  2  2π 1   3 ,− 4  2  ,−   3 4 π



5π 2

x

2 + cos x ≠ 0 cos x ≠ −2 ( ∀x ∈ R ) . sin ( − x ) − sin x sin x 2.) Parnost y ( − x ) = 2 + cos( − x ) = 2 + cos x = − 2 + cos x = −( y ( x ) ) .Neparna funkcija. 3.) Periodičnost. Periodična sa periodom 2kπ .

1.) Domen D :

4.) Nule funkcije y=0

5.) Znak funkcije

(k ∈ Z)

x = kπ

sin x = 0 0

sin x 2 + cos x

0

+ +

0

y

+

0

+

0

0

-

0

6.) Prvi izvod funkcije y′ =

cos x( 2 + cos x ) + sin x( sin x )

y′ = 0

( 2 + cos x )

2

2cosx + 1 = 0

=

2 cos x + cos 2 x + sin 2 x

( 2 + cos x )

cos x = − x1 =

2

2 cos x + 1

( 2 + cos x ) 2

1 2

2π + 2kπ 3

x2 =

7.) Znak prvog izvoda Ekstremi :

4π + 2kπ 3

0

3 3 3 2 y  2π  = = 2 = 3 max   3  1  3  2 + −  2  2 1 1 − − 2 = 2 =− 1 ≈ 2 y  4π  = min   3 4− 3 4− 3 5  3  2− 2 2 y ′′ =

=

2 cos x + 1

( 2 + cosyx′) 2

+ 0 +

- 0 +

+ +

+

-

+

0

0

y

− 2 sin x( 2 + cos x ) 2 + 2( 2 + cos x ) ⋅ sin x( 2 cos x + 1)

( 2 + cos x ) 4

( 2 + cos x )[ − 4 sin x − 2 sin x cos x + 4 sin x cos x + 2 sin x ] = 2 sin x cos x − 2 sin x = 2 sin x( cos x − 1) ( 2 + cos x ) 4 ( 2 + cos x ) 3 ( 2 + cos x ) 3 y sin x y ′′ = 0 sin x = 0 cos x = 1 y= 2 + cos x x = kπ x=0 x = 2π y ′′ =

Prevojne tačke 8.) Grafik

− 2π 67





4π 3

−π

 2π 3     3 , 3   

2π 3 0

π 2

2π 3

π

4π 3

 4π 1   ,   3 4− 3



x

112. y = x 2 ⋅ (1 − ln x ) 1.) Domen D : x > 0 x ∈ ( 0,+∞ ) . 2.) Parnost. Nije ni parna ni neparna funkcija. 3.) Periodičnost. Funkcija nije periodična. 4.) Nule funkcije y=0

x2 = 0 ∉ D



ln x = 0 ln  x = 1 x = 1 = 

5.) Znak funkcije

0

+∞

1− ln x

+

x2

+

y

+

6.) Prvi izvod funkcije

0

+

0

-

 1 y ′ = 2 x ⋅ (1 − ln x ) + x 2 ⋅  −  = 2 x(1 − ln x ) − x  x y ′ = x ⋅ ( 2 − 2 ln x − 1) = x ⋅ (1 − 2 ln x ) y′ = 0 ⇒ x = 0 ∉ D ∧ 1 − 2 ln x = 0 2 ln x = 1 1 ln  x = 2 x=

1 2

7.) Znak prvog izvoda

=  0

1− 2 ln x

+

x

+

y′

+

y

68

+∞

0

+

0

-

 y max (  ) = 2

 x  xy−⋅=+20ln1[]() ′ ′  1 xy−=2ln1 ′ xy−=1ln2 ′

− 2 ln x − 1 = 0 1 ln x = − 2

Prevojna tačka



x =

1 2

1

=



8.) Asimptote 1 1 − ln x − x −1 ⋅ x 3 x2 2 x x ⋅ (1 − ln x ) = lim = lim = lim = lim =0 lim −3 1 2 x →0 x →0 x →0 − 2 x x →0 x →0 2 x2 −

9.) Grafik

y = x 2 ⋅ ( 1 − ln x )

y

5 4 3

   ,  2 

2 1

x 0 1 1 

113. y =

x +1 x+2

1.) Domen D :

x+2≠0

 2

3

4

x ≠ −2

− x +1

 1− x 1− x = =− 2.) Parnost y ( − x ) = nije ni parna ni neparna funkcija. − x + 2 − ( x − 2) x−2

3.) Periodičnost. Nije periodična. 4.) Nule funkcije. Nema nula. 5.) Znak funkcije

-∞

x+2 y

69

-2

-

0

+∞

+

+

+

-

+

6.) Prvi izvod funkcije y′ =

( )′ x +1

( x + 2) ′

y′ = 0

=

( x + 2) 2

x +1 = 0

x = −1

7.) Znak prvog izvoda -∞ 

( )=

x +1 ⋅( x + 2 ) − 1 ⋅ x +1

-2

(

x +1

≠ 0,

-1

x+1

+ -

+ -

( x + 2) 2

+

+

+

-

+

-

y′

x +1 > 0

)

+∞

x +1

0

( x + 2 − 1) = x+1 ( x + 1) ( x + 2) 2 ( x + 2) 2

x +1

+ +

1 y min ( −1) = = 1 1

y

( x + 2) 2 ⋅ (x+1 ⋅ ( x + 1) + x+1 ) − 2( x + 2) x+1 ⋅ ( x + 1) ( x + 1) 4 ( x + 2) ⋅ (x+1 ) ⋅ [ x 2 + x + 2 x + 2 + x + 2 − 2 x − 2] = x+1 ⋅ ( x 2 + 2 x + 2) y ′′ = ( x + 2) 4 ( x + 2) 3 y ′′ =

y ′′ > 0

Funkcija ima minimum. 8.) Asimptote

lim y = lim x → −∞

x →−∞

x +1 L. P

lim x → +∞ x + 2

=

x +1 L.P x +1 1 1 = lim = lim −( x +1) = = 0 horizontalna asimptota. x + 2 x→−∞ 1 ∞ x →−∞ 

x +1 ∞ = =∞ lim 1 x →+∞ 1

x +1 −1 1 1 = = = = −∞ lim − 0  ⋅ ( − 0) − 0 x → −2 − 0 x + 2 x +1 −1 1 1 = = = = +∞ lim + 0  ⋅ ( + 0) + 0 x → −2 + 0 x + 2

70

9.) Grafik

y

( − 1,1) -3

-2

x +1 y= x+2

1 -1

0 -1

1

2

x

y=0

-2 -3 x= - 2

114. y =

( x − 2) 3

x2 + x +1 1.) Domen D := R

2.) Parnost y ( − x ) =

x ∈ ( − ∞,+∞ )

( − x − 2) 3 = − ( x + 2) 3 funkcije nije ni parna ni neparna. ( − x) 2 − x + 1 x 2 − x + 1

3.) Periodičnost. Nije periodična. 4.) Nule funkcije y=0

x−2=0

x=2

5.) Znak funkcije

-∞

( x − 2) 3 x2 + x +1

6.) Prvi izvod funkcije y′ = y′ =

71

(

)

y

2

+ +

2

( x − 2 ) 2 ( x 2 + 6 x + 5)

(x

2

)

+ x +1

2

)

+ x +1

2

+ +

-

3( x − 2 ) 2 ⋅ x 2 + x + 1 − ( 2 x + 1) ⋅ ( x − 2 ) 3

(x

0

+∞

0 =

+

( x − 2 ) 2 [3 x 2 + 3 x + 3 − 2 x 2 + 4 x − x + 2 ]

(x

2

)

+ x +1

2

y′ = 0

x 2 + 6x + 5 = 0 x 2 + x 3 = −6

x-2 = 0 x1 = 2

x 2 ⋅ x3 = 5 x 2 = −1 y′ =

x 3 = −5

( x − 2) 2 ⋅ ( x + 5) ⋅ ( x + 1)

(x

2

)

+1

2

7.) Znak prvog izvoda

-∞

( x − 2) 2 ( x + x + 1) 2

2

x+5 y′

-5

+

-1

+

- 0 + - 0 + 0 - 0

2

+

+∞

0

+

y max ( −5 ) =

+ + + + + + + 0 +

y min ( −1)

− 343 21

( − 3) 3 = 1

= −27

y prev ( 2 ) = 0

y

8.) Asimptote

( x − 2) 3

3

 2 1 −  3 3 2 ( x − 2) / : x  x = 1 =1 x + x + 1 k = lim = lim 3 = lim 2 3 x 1 x →∞ x →∞ x + x + x / : x x →∞ 1 + 1 + 1 2 x x 3 3 2 3  ( x − 2)   x − 6 x + 12 x − 8 − x − x 2 − x  − 7 x 2 + 11x − 8  = lim n = lim  2 − x  = lim  = 2 2  x + x + 1 x + x + 1 x + x + 1  x →∞  x → ∞ x → ∞     11 8 −7+ − 2 −7 x x = lim = = −7 1 x →∞ 1 + 1 + 1 x x2 ( x − 2) 3 y = x − 7 kosa asimptota funkcije y = . x -1 0 6 1 x2 + x +1

Funkcija presijeca kosu asimptotu.

y = x−7 y=

( x − 2) 3 x2 + x +1

( x − 2) 3



( x − 2) 3 x2 + x +1

− x−7 = 0 ⇒ x2 + x +1 18 x − 1 =0 18 x − 1 = 0 x2 + x +1

y

= x−7 x 3 − 6 x 2 + 12 x − 8 − x 3 + 6 x + 6 x 2 + 7 =0 x2 +1 1 x= 18

1   ,−7  tačka presjeka kose asimptote i funkcije.  18 

72

-8

-7

-1

-6

9.) Grafik

y

y=

-5

-1

( 2,0)

0

( x − 2) 3 x2 + x + 1

( 7 ,0 )

y=x-7

x

( 0,− 8)  − 343   − 5,  21  

x 115. y = x +1

1.) Domen D : 2.) Parnost y ( − x ) =

( − 1−, 27) x +1 ≠ 0

-27

x ≠ −1

−x

 − x − x = =− nije ni parna ni neparna funkcija. − x + 1 − ( x − 1) x −1

3.) Periodičnost. Nije periodična. 4.) Nule funkcije. Nema nula.

73

-16

-∞

5.) Znak funkcije

-1

x +1

-

x

+

+

-

+

y

6.) Prvi izvod funkcije y′ =

(  )′ x

( x + 1) ′

y′ = 0

=

0

( ) =  ( x + 1 − 1) =

x ⋅( x + 1) − 1 ⋅ x

( x + 1) 2

x ⋅ x = 0

+∞

x=0

x

( x + 1) 2

+

x ⋅ x

( x + 1) 2

x = 0 y =1

7.) Znak prvog izvoda -∞ 

-1

0

+∞

x

x

+ -

( x + 1) 2

+ -

+ 0

0

+ +

+

+

+

-

1 y min ( 0 ) = = 1 1

y

Funkcija ima minimum. 8.) Asimptote

lim y = lim x → −∞

x →−∞

 x L. P x 1 1 = lim = −∞ = ∞ = = 0 horizontalna asimptota. x + 1 x→−∞ 1 ∞ 

 L. P x ∞ = lim = =∞ lim 1 x → +∞ x + 1 x → +∞ 1 x

x −1 1 1 = = = = −∞ lim − 0  ⋅ ( − 0) − 0 x →−1− 0 x + 1 x −1 1 1 = = = = +∞ lim + 0  ⋅ ( + 0) + 0 x →−1+ 0 x + 1

74

9.) Grafik y

x y= x +1 ( 0,1) -3

-2

-1

1 0

1 -1 -2 -3

x= - 1

Integrali

∫ f ( x ) = F( x ) + C F( ′x ) = f ( x )

Osnovni tablični integrali x n+1 +C n +1 ∫ sin xdx = − cos x + C n ∫ x dx =

∫ cos xdx = sin x + C x x ∫  dx =  + C dx ∫ sin 2 x = −ctgx + C dx

∫ cos 2 x = tgx + C x ∫ a dx =

dx

∫ 1− x2

= arcsin x + C

∫ 1+ x2

= arctgx + C

dx

∫ 75

ax +C ln a

dx = ln x + C x

2

x

y=0

116.

∫ (x

3

)

+ 2 x 2 − x − x dx = ∫ x 3 dx + 2∫ x 2 dx − ∫ xdx − ∫ x dx =

x4 x3 x 2 2 x3 +2 − − +C 4 3 2 3

117. x−3= t ( x − 3) 16 dx = = ∫ 3 t 16 dt = ∫ dx = dt

∫3

16 t 3 dt

=

16 +1 t3

19

16 +1 3

( x − 3) 3 +C = 19 3

3 3 ⋅ ( x − 3) 19 + C 19

+C =

118. x −3= t 2 1 x  x  ∫ sin 2 − 3dx = 2 dx = dt = 2∫ sin tdt = 2 ⋅ ( − cos t ) + C = −2 ⋅ cos 2 − 3 + C dx = 2dt

119. dx

∫ ( 2 x − 5) 3

dt 2x − 5 = t 1 1  1  −1 = 2dx = dt = ∫ 23 = ∫ t −3 dt = ⋅  − 2  + C = +C 2 2  2t  t 4 ⋅ ( 2 x − 5) 2 1 dx = dt 2

120.

1 1 1 A B C D Ex + F = 2 2 = 2 = + 2 + + + 2 = 4 2 2 x x x −1 x +1 x +1 x x − 1 x x − 1 x + 1 x ( x − 1)( x + 1) x + 1

)( ) Ax ( x − 1) + B ( x − 1) + Cx ( x + 1) ( x = 2

(

)

4

=

(

4

2

(

(

)

)

(

)

(

)

+ 1 + Dx 2 ( x − 1) x 2 + 1 + ( Ex + F ) x 2 x 2 − 1 = x 2 ( x − 1)( x + 1) x 2 + 1

)(

2

) (

(

)

)(

)

Ax 5 − Ax + Bx 4 − B + Cx 3 + Cx 2 x 2 + 1 + Dx 3 − Dx 2 x 2 + 1 + Ex 5 − Ex 3 + Fx 4 − Fx 2 = x 2 ( x − 1)( x + 1) x 2 + 1

(

)

x 5 ( A + C + D + E ) + x 4 ( B + C − D + F ) + x 3 ( C + D − E ) + x 2 ( C − D − F ) + x ( − A) − B x 2 ( x − 1)( x + 1) x 2 + 1 − B = 1 (1) − A = 0 ( 2) C − D − F = 0 ( 3) C + D − E = 0 ( 4) B + C − D + F = 0 ( 5) A + C + D + E = 0 ( 6) =

A=0 B = −1

(

( 3) − ( 5)



− B − 2F = 0 - 2 F = -1

76

)

⇒F=

1 2

( 4) − ( 6)

C + D-E = 0 − A−C − D− E = 0 − A − 2E = 0 − 2E = 0 E=0 ( 3) + ( 4) ⇒ 2C − F − E = 0 1 2C = + 0 2 1 C= 4 ( 4) ⇒ D = E −C 1 D=− 4 1 1 1 1 − 2 + − + = 2 4( x − 1) 4( x + 1) 2 x + 1 x = =



(

)

(

(

)

)

(

)

(

2

2

(

)

4 x ( x − 1)( x + 1) x + 1 2

2

− 4x 4 + 4 + x5 + x3 + x 4 + x 2 − x5 + x 4 − x3 + x 2 + 2x 4 − 2x 2 4 = 2 4 2 4 4x x − 1 4x x − 1

(

)

(

 1 dx 1 1 1 ∫ x 2 x 4 − 1 = ∫  − x 2 + 4( x − 1) − 4( x + 1) + 2 x 2 + 1 1 1 x −1 1 = + ln + arctgx + C x 4 x +1 2 dx 121. ∫ 2 = arctgx + C x +1

(

)

(

)

dx

∫ x2 + x +1 = ∫ 

dx 2

1 3 x +  + 2 4 

4 3 2 3 ⋅ ⋅ arctgt + C = arctg 3 2 3

122. 77

=∫

∫1+

xdx 1+ x

dx 2   1  x +  3  2 ⋅ 4  3     2 

1 2 3 2

x+

3 dt 1 4 = dx = dt = ∫ 22 = 3 t +1  3  2 + 1  3 dt  dx = 2 

1 2 + C = 2 ⋅ arctg  2 x + 1  + C   3 3  3  2

x+

)

 x − 2+1 1 1 1  dx = − + ln x − 1 − ln x + 1 + arctgx + C =  − 2 + 1 4 4 2 

t=

=

)=

− 1 ⋅ 4 ⋅ x − 1 + 1 ⋅ x ⋅ x + 1 ( x + 1) − 1 ⋅ x 2 ⋅ x 2 + 1 ( x − 1) + 2 x 2 x 2 − 1 4

∫1+

xdx



1− 1+ x

1+ x 1− 1+ x

= ∫ t dt = ∫

1 t 2 dt

=

=∫

1 +1 t2

1 +1 2

=

(

)

(

)

(

)

1+ x = t x ⋅ 1− 1+ x = −1∫ 1 − 1 + x dx = ∫ 1 + x − 1 dx = = dx = dt 1−1+ x 3 t2

3 2

=

2 ⋅ 3

(1 + x ) 3 − x + C

123. 1− x = t 1− x = t2 dx − 2tdt dt  1 ∫ (1 + x ) 1 − x = − dx = 2tdt = ∫ 2 − t 2 t = −2∫ 2 − t 2 = − 2 2 2 dx = −2tdt

(

)

dt



2 −t

+

1 2

∫ 2

1− t2 = x 2

=

2 2

⋅ ln 2 − t −

1 = 2 −t2

2 2 2

1

(

2 −t

)(

2 +t

)

⋅ ln 2 + t = =

A 2 −t

+

1 2

2 −t

ln

B 2 +t

2 +t =

+C =

(

A 2 + At + 2 B − Bt t ( A − B ) + 2 A + 2 B = 2 −t2 2 −t2 A− B = 0 /⋅ 2 2 A + 2B = 1

2 2A = 1

B=



78

1 2 2

=

2 4

2 4

2−x=t − dt = − dx = dt = ∫ = − ln t = − ln 2 − x t 2−x dx = − dt dx

2

) (

2 − 1− x

⋅ ln

)

2 + 1− x

A 2 +t + B 2 −t = 2 −t2

=

A=

1

+C

 = 2 +t dt

124. x +1 = t6

xdx

∫ 3 x +1 − =∫

x +1

= dx = 6t 5 dt = ∫ x = t 6 −1

(

(t 3

)

6

− 1 6t 5 dt

t6 − t6

)

=∫

(

)

(

)

6t 3 ( t − 1) t 5 + t 4 + t 3 + t 2 + t + 1 dt = −6∫ t 8 + t 7 + t 6 + t 5 + t 4 + t 3 dt = − ( t − 1)

= −6

(

)

t9 t8 t7 t6 t5 t4 −6 −6 −6 −6 −6 +C = 9 8 7 6 5 4

− 26 ( x + 1) 9 36 ( x + 1) 8 66 ( x + 1) 7 66 ( x + 1) 5 36 ( x + 1) 4 = − − − ( x + 1) − − = 3 4 7 5 2 2 ( x + 1) 3 − 3 3 ( x + 1) 4 − 6 ( x + 1) 6 x + 1 − x − 1 − 6 6 ( x + 1) 5 − 3 3 ( x + 1) 2 + C =− 3 4 7 5 2

125. x4 1 1 = 1 + = 1 + = x4 −1 x2 −1 x2 +1 ( x − 1)( x + 1) x 2 + 1 = = =

(

(

)

)(

)

(

(

)

)

A( x + 1) x 2 − 1 + B( x − 1) x 2 + 1 + ( Cx + D )( x + 1)( x − 1) = ( x − 1)( x + 1) x 2 + 1

(

A x3 + x + x 2

(

) + 1) + B ( x + x − x − 1) + Cx ( x − 1)( x + 1) ( x + 1) 3

2

3

− Cx + Dx 2 − D

2

)

x 3 ( A + B + C ) + x 2 ( A − B + D ) + x( A + B − C ) + A + B − D = x4 −1 A + B + C = 0 (1) A − B + D = 0 ( 2) A + B − C = 0 ( 3) A − B − D = 1 ( 4)

=

(

(1) − ( 3)

2C = 0

( 2) − ( 4)

D + D = −1

(1) − ( 4)

)

⇒ C=0 D=−

2 B + C + D = −1 1 2 B = −1 + ⇒ 2 1 A+ B +C = 0 ⇒ A− +0 = 0 4

79

=

Ax 3 + Ax + Ax 2 + A + Bx 3 + Bx − Bx 2 − B + Cx 3 − Cx + Dx 2 − D = x4 −1

(

1 2 1 4 1 ⇒ A= 4 B=−

(

)

6t 5 t 6 − 1 dt 6t 5 t 6 − 1 dt 6t 3 t 6 − 1 = = ∫ t 2 (1 − t ) ∫ (1 − t ) = t2 − t3

1 1 1 1 1 1 = 1 + 4 − 4 − 22 = 1 + − − 2 x −1 x +1 x +1 4( x − 1) 4( x + 1) 2 x + 1 dx ∫ x ± a = ln x ± a + C a = const.   x4 1 1 1 1 1 1 ∫ x 4 − 1 dx = ∫ 1 + 4( x − 1) − 4( x + 1) − 2 x 2 + 1 dx = x + 4 ln x − 1 − 4 ln x + 1 − 2 arctgx + C =

(

(

)

)

1 x −1 1 = x + ln − arctgx + C 4 x +1 2

126. x +1

x( x − 1) 3 = = =

(

A B C D A( x − 1) 3 + Bx( x − 1) 2 + Cx ( x − 1) + Dx = + + + = = x ( x − 1) ( x − 1) 2 ( x − 1) 3 x( x − 1) 3

)

(

)

A x 3 − 3x 2 + 3 x − 1 + Bx x 2 − 2 x + 1 + Cx 2 − Cx + Dx x( x − 1)

3

=

Ax 3 − 3 Ax 2 + 3 Ax − A + Bx 3 − 2 Bx 2 + Bx + Cx 2 − Cx + Dx x( x − 1) 3

=

x 3 ( A + B ) + x 2 ( C − 3 A − 2 B ) + x( 3 A + B − C + D ) − A x( x − 1) 3

A+ B = 0 C − 3 A − 2B = 0 3A + B − C + D = 1 − A =1 A = −1 B =1 C +3−2 = 0 C = −1 − 3 +1+1+ D = 1 D=2 A B C D 1 1 1 1 = + + + = − + − + x x − 1 ( x − 1) 2 ( x − 1) 3 x x − 1 ( x − 1) 2 ( x − 1) 3 x +1 1 1 1 dx ∫ x( x − 1) 3 dx = ∫ − x dx + ∫ x − 1 dx − ∫ ( x − 1) 2 dx + ∫ ( x − 1) 3 = dx

=

∫ ( x − 1) 2 dx

∫ ( x − 1) 3

x −1 = t dt t − 2+1 1 1 −2 = = = t dt = =− =− +C  ∫ ∫ 2 − 2 +1 t x −1 t dx = dt  = x −1 = t dt t −3+1 t −2 1 −1 −3 = +C  = ∫ 3 = ∫ t dt = − 3 + 1 = − 2 = − 2 = t t 2( x − 1) 2 dx = dt 

= − ln x + ln x − 1 +

80

1 1 x − 1 2( x − 1) − 1 x −1 2x − 3 − + C = ln + + C = ln + +C 2 2 x − 1 2( x − 1) x x 2( x − 1) 2( x − 1) 2

127.



(1 − x ) 2 dx = x⋅ x

3 − +1 x 2

=



3 +1 2

−2



1 − 2x + x 2 3 x2

1 − +1 x 2



1 +1 2

  1 2x x 2 dx = ∫  3 − 3 + 3  2 x2 x2 x

1 x2

+

1 +1 2

=

x





1 2

1 2

− 2⋅

1 x2

1 2

+

3 x2

3 2

 1 1   −3 −   2 2 2 dx = ∫  x − 2 ⋅ x + x dx =     2

+C = −

x

−4 x +

2 3 x +C 3

128.



(x

2

)

(

2

)

1 x2

−1 x x x −1 ⋅ dx = ∫ 2 x x2 3

+1

5 − +1

1 ⋅ x4

dx = ∫ 7

(x

2

)

−1 x2 −

3 x4

dx = ∫

11 x4

− x2

3   11  x 4 x4  dx = ∫  2 − 2 dx = x   x  

3 x4

1

5  3 −  x4 x 4 x4 x 4 4 4 7 4 = ∫  x 4 − x 4 dx = − +C = − = ⋅ x + 4 +C   3 5 7 1 7 x   +1 − +1 − 4 4 4 4 2 x +3 4   129. ∫ 2 dx = ∫ 1 + 2 dx x −1 x −1  4 4 A B A( x + 1) + B ( x − 1) Ax + A + Bx − B x( A + B ) + A − B = = + = = = 2 x − 1 ( x − 1)( x + 1) x − 1 x + 1 x2 −1 x2 −1 x2 −1 A− B = 4 A+ B = 0 2A = 4 A=2 B = −2 x2 + 3 2 2  x −1  ∫ x 2 − 1 dx = ∫ 1 + x − 1 − x + 1 dx = x + 2 ln x − 1 − 2 ln x + 1 + C = x + 2 ln x + 1 + C

130.

∫ =∫

81

 1+ x2  1 − x 2  1+ x2 dx = ∫  + dx = ∫  + 2 2 4   1− x4  1 + x 1 − x 1− x    dx = arcsin x + ln x + x 2 + 1 + C 2 1+ x

1+ x2 + 1− x2 1− x4 dx 1− x

2

+∫

(

)(

)

1− x2 1+ x2 1− x2

(

)(

)

 dx =  

131. x2 +1 = t − x /2

(

)

2t ⋅ 2t − 2 t 2 − 1 t 2 +1 dx = dt x + 1 = t − 2tx + x dx dx 4t 2 2t 2 2 = = = = 1− t ∫ x 2 + 1 ∫ 2t 2 − t 2 + 1 dt = 2t 2 + 2 t2 +1 x2 +1 x = dx = dt = dt 2t 2t 4t 2 2t 2 t = x + x2 +1 2



=∫

(

)

2

2

2t t 2 + 1 dt dt = = ln t + C = ln x + x 2 + 1 + C ∫ 2 2 t 2t t + 1

132.

(

)

x 2 + 2x + 3 = x + t / 2 x 2 + 2 x + 3 = x 2 + 2 xt + t 2 2 x − 2 xt = t 2 − 3 x( 2 − 2t ) = t 2 − 3

− t 2 + 2t − 3

t2 − 3 2(1 − t ) 2 =∫ 2 dt = ∫ x x 2 + 2 x + 3 = x = 2 − 2t t −3  t2 −3  ⋅ +t 2t ( 2 − 2t ) + 2 t 2 − 3 2 − 2t  2 − 2t  dx = dt ( 2 − 2t ) 2 dx

(

dx = dx = dx =

4t − 4t 2 + 2t 2 − 6

( 2 − 2t ) 2

− 2t 2 + 4t − 6

(

( 2 − 2t ) 2

dt

dt

) dt

2 − t 2 + 2t − 3 2 2 (1 − t )

2

− t 2 + 2t − 3

=∫

)

(

)

2 − t 2 + 2t − 3 dt 2(1 − t ) 2 dt = ∫ 2 dt = 2 ∫ = 2 2 2 2 t − 3 t − 3 + 2t − 2t t − 3 − t + 2t − 3 t− 3 t+ 3 ⋅ 2(1 − t ) 2(1 − t )

(

)(

)

(

1   1   2 2 2 3 2 3   = 2∫ − dt = ln t − 3 − ln t + 3 + C = t − 3 t + 3 2 3 2 3     =

82

1 3

⋅ ln

x 2 + 2x + 3 − x − 3 2

x + 2x + 3 − x + 3

+C

)(

)

1 A B At + A 3 + Bt − B 3 t ( A + B ) + A 3 − B 3 = + = = t −3 t − 3 t + 3 t− 3 t+ 3 t− 3 t+ 3

(

2

A+ B = 0

)(

)

(

)(

)

/⋅ 3

A 3 − B 3 =1 2 3A = 1 1 A= 2 3



B=−

1 2 3

133.

∫ 3

x  5 −  = t 3  −5 2 +1 − 5 3 − dx 1 − 3dt t t 3 9 = − dx = dt = ∫ = −3∫ t 3 dt = −3 ⋅ + C = 3⋅ +C = +C 3 5 5 2 5 2 3 t x x     − +1 23  5 −  5 −  dx = −3dt 3 3 3 3  

134.



dx 3 − 5x 2

x

=

3 5 1 3 5

dx  5x 2 31 − 3 

   

=∫

dx 5x 2 3 1− 3

=∫

dx 3 1−

=

x2 3   5

1

dx

∫ 3

    x   1−  3    5

2

2

=

=t 3 dx = dt =

dx =

83

=∫

3 dt 5

1

∫ 3

5

dt

1− t2

=

1 3



3 5

⋅∫

dt 1− t2

=

1 5

arcsin t + C =

1 5

arcsin

5x 3

+C

135. x

dx



7 − 11x 2

1

=

7

⋅∫

=∫

dx  11  71 − x 2  7  

7 ⋅ 1−

=

x2  7     11   

1 7

dx

⋅∫

    x   1−  7     11 

2

∫3

=∫

(

(1 − 2 sin

2

)

x + sin 4 x cos xdx 8

( sin x ) 3

8 − +1 t 3

8 − +1 3

)

(

2

)

7 11 dx =

dx = dt =

7 dt 11

2

− 2⋅

2 − +1 t 3

2 − +1 3

+

4 +1 t3

4 +1 3

8 2 4   8 8  −8 − − 2− 4−  3 3 3   = ∫ sin x − 2 ⋅ ( sin x ) 3 + ( sin x ) 3 ⋅ cos xdx = ∫ t − 2t + t 3 dt =        

+C =

t



5 3

5 − 3

− 2⋅

1 t3

1 3

+

7 t3

7 3

+C = −

(

3

∫  



2 x − 53 x +

3

5

2  dx dx = ∫ 3 2 x dx − 5∫ 3 x dx + 2 ∫ =  5 4x 4 x  

 2x   3 =t    2 2x x 2 3 3 3 2x  3  dx = ∫  dx = dx = dt  = ∫ t dt = ⋅  3 = 3 2 x 3  2 2 2   3 dx = dt  2  

  3 x = t    1 t 1 t 1 3x 3x t dt ∫  dx = 3dx = dt  = ∫  3 = 3 ∫  dt = 3  = 3   1  dx = dt  3  

3 5

53 sin x

137.

84

=

sin x = t cos 2 x ⋅ cos xdx 1 − sin 2 x ⋅ cos xdx dx = =∫ = = ∫ 8 8 8 cos xdx = dt sin x ( sin x ) 3 ( sin x ) 3

cos 5 x

=

2

=t

7 dt dt 1 1 x 1 11x 11 = 1 ⋅ = arcsin t + C = arcsin +C = arcsin +C ∫ 2 2 11 11 11 7 11 7 1− t 1− t 11

136.

=

dx

=∫

7 11 1

)

− 63 sin x +

33 sin 7 x + C 7

 4x  − 5 = t    4x 4 − dx dx 4 5 5 5 −5x t t   5 ∫ 5 4 x = ∫ 4 x = ∫  dx = − 5 dx = dt  = ∫  ⋅ − 4 dt = − 4 ⋅ ∫  dt = − 4  =   5 dx = − 5 dt  4   3 3 2x 1 3x 5 1 3 ⋅ 3 2 x 5 3 x 5 1 = ⋅  − 5⋅ ⋅ + 2⋅− ⋅ +C = −  − ⋅ +C 5 5 2 3 4 4 x 2 3 2 4 x

138. x +1 =t x x − 1( x + 1) dx = dt x2 1 − 2 dx = dt x 1 2 x +1 dt 2 2 dx = − x dt dx = = ∫ ( t − 1) t  − 2 x  ( t − 1) x + 1 = xt x(1 − t ) = −1 1 x= ( t − 1) 1 x2 = ( t − 1) 2

1 ∫ x2

  = −∫  

1 t 2 dt

1 +1 t2

Parcijalna integracija

( u ⋅ v ) ′ = u ′ ⋅ v + u ⋅ v′ d ( u ⋅ v ) = v ⋅ du + u ⋅ dv

∫ u ⋅ dv = u ⋅ v − ∫ v ⋅ du

′ ∫ d ( u ⋅ v ) = ∫ v ⋅ du + ∫ u ⋅ dv

( u ⋅ v ) − ∫ v ⋅ du = ∫ u ⋅ dv

139.

x=u

∫ x ⋅  dx = dx = du x

x dx = dv v = ∫  dx =  x

x

= x ⋅ x − ∫ x dx = xx − x + C = x ⋅ ( x − 1) + C

140. ln x = u ∫ ln xdx = 1 dx = du x

85

dx = dv x=v

3

2  x + 1 =− =−   +C 1 3  x  +1 2

1 = x ⋅ ln x − ∫ x ⋅ ⋅ dx = x ⋅ ln x − x + C = x ⋅ ( ln x − 1) + C x

2 141. ∫ sin xdx I način :

∫ sin

2

xdx = ∫ sin x ⋅ sin x ⋅ dx =

sin x = u cos xdx = du

sin xdx = dv = I = sin 2 x = - cos x = v

(

)

= − sin x cos x + ∫ cos 2 xdx = − sin x cos x + ∫ 1 − sin 2 x dx = − sin x cos x + x − ∫ sin 2 xdx = I = − sin x cos x + x − I 2 I = x − sin x cos x x − sin x cos x I= +C 2

II način : sin 2 x + cos 2 x = 1 cos 2 x − sin 2 x = cos 2 x 2 sin 2 x = 1 − cos 2 x 1 − cos 2 x sin 2 x = 2 1 − cos 2 x 1 1  2 ∫ sin xdx = ∫ 2 dx = ∫  2 − 2 ⋅ cos 2 x dx =   2 x = t    1 1 1 1 1 1 1 1 = ∫ cos 2 xdx = 2dx = dt  = ∫ cos tdt = sin t = sin 2 x = x − ⋅ sin 2 x + C = x − sin 2 x + C 2 2 2 2 2 2 2 4  1  dx = dt  2  

142.



ln x = u

ln xdx = 1 x2 dx = du x

=−

1 dx = dv 1 1 − ln x x2 = − ⋅ ln x + ∫ 2 dx = + ∫ x − 2 dx = x x 1 x − =v x

ln x x −2+1 − ln x − 1 + +C = +C x − 2 +1 x

143. 2 ∫ x arctgxdx =

86

arctgx = u 1 dx = du 1+ x2

x 2 dx = dv 3

x =v 3

=

x3 1 x3 ⋅ arctgx − ∫ dx = 3 3 1+ x2

  x2 + 1 = t    x3 x  x2 xdx  ∫ 1 + x 2 dx = ∫  x − 1 + x 2 dx = 2 − ∫ x 2 + 1 = 2 xdx = dt  = 3 2  dt  = x arctgx − 1 ⋅  x − 1 ln x 2 + 1  + C    xdx =  3 3 2 2  2   dt x2 x2 1 x2 1 = −∫ 2 = − ln t = − ln x 2 + 1 2 t 2 2 2 2

(

)

144.

dx



x

x

x

∫ sin x = sin x =  2 sin 2 cos 2  = 2tg 2 ⋅ cos

2

x = 2

2tg 1 cos 2

= cos x = cos 2

x x − sin 2 2 2

x 2 = x 2

2tg

x 2

x x sin + cos 2 2 2 x cos 2 2 2

x 1 − tg 2 cos x  2 x 2 x 2 = ⋅ = 1 − tg =  ⋅ cos 1 cos x  2 2 1 + tg 2 x cos 2 2 1 − tg 2

t = tg

=

2tg

x 2

x tg +1 2 2

x 2 = x 2

x 2

x 2dt 2 2 sin x dt x = tgx = = = x = 2arctgt = ∫ 1+t = ∫ = ln t + C = ln tg + C x 2t cos x t 2 1 − tg 2 1 2 2 dx = 2 ⋅ dt 1+t 1+ t2 2t sin x = 1+ t2 x 2tg 2

87

arctgt =

=

145.

cos x =

1− t2 1+ t2

1 − t 2 2dt ⋅ 2 2 1 + t 1 + t 2 =  1 − t =∫ ∫  1 + t 2 1 + t 2 2 1+ t2

x cos xdx 2 ∫ 1 + cos x = 2dt dx = 1+ t2 t = tg

1 + cos x = 1 +

 dt =  

1− t2 1+ t2 +1− t2 2 = = 2 2 1+ t 1+ t 1+ t2

1  x x x   x = arctgt − ∫ 1 − 2 dt = arctgt − t + arctgt + C = 2arctg  tg  − tg + C = 2 ⋅ − tg + C = 2 2 2  t + 1  2 x = x − tg + C 2

146.

x x x x  sin x =  2 sin cos  = 2tg ⋅ cos 2 = 2 2 2 2 

dx 2 x 2 x ∫ 3 + 5 cos x = cos x = cos 2 − sin 2

t = tg

x 2

x 2 x = 2arctgt 1 dx = 2 ⋅ dt 1+t2 2t sin x = 1+t2 1−t2 cos x = 1+t2 arctgt =

88

2tg 1

x 2 =

x cos 2 2

2tg sin 2

x 2

x x + cos 2 2 2 2 x cos 2

cos x  x x ⋅ = 1 − tg 2  ⋅ cos 2 = cos x  2 2

2tg = tg 2

x +1 2

x 1 − tg 2 2 = 1 1 + tg 2 x cos 2 2

1 − tg 2

x 2

x 2 x 2

=

2dt 2dt 2 2dt dt 1+ t2 = ∫ 1+ t 2 = ∫ =∫ = 2∫ = 2 2 2 2 1− t 31+ t + 5⋅ 1− t 3 + 3t + 8 − 5t 8 − 2t 2 3+ 5⋅ 1+ t2 1+ t2 1 4 dt = 1 dt = − 1 du = − 1 ln 2 − t 1   1   2−t 4 ∫ 2−t 4∫ u 4 dt dt 4 4   = 2∫ = = + dt = = ∫ ( 2 − t )( 2 + t ) ∫  2 − t 2 + t  ∫ 2 − t = u  2 4 −t2   − dt = du      dt = −du 

(

(

)

(

)

)

x 1 1 1 2+t 1 2 +C = − ln 2 − t + ln 2 + t = ln = ln x 4 4 4 2−t 4 2 − tg 2 1 A B A( 2 + t ) + B ( 2 − t ) 2 A + At + 2 B + Bt t ( A + B ) + 2 A + 2 B = + = = = ( 2 − t )( 2 + t ) 2 − t 2 + t ( 2 − t )( 2 + t ) ( 2 − t )( 2 + t ) ( 2 − t )( 2 + t ) A+ B = 0 2 A + 2B = 1 2A + 2A = 1 4A = 1 1 1 A= B= 4 4 2 + tg

147. dx

∫ 7 cos 2 x + 3 sin 2 x

dx 1 dx 2 2 : cos x 1 + tg 2 x dx cos x cos x = = = = : cos 2 x ∫ 7 + 3tg 2 x ∫ 7 + 3tg 2 x ∫ 3 + 3tg 2 x 2

(

)

tgx = t x = arctgt dt 1+ t2 dt dt 1 dt dx 1+ t2 = = =∫ =∫ = ∫ = dt ∫ 3 2 2  3  7 7 + 3t 7 + 3t cos x  7 ⋅ 1 + t 2   7 dt   t dx = 1+  2  7 1+ t   3

(

)

7 du 1 1 7 du 7 7 3t 3 = ∫ = ⋅ ⋅∫ = arctgu = arctg +C = 2 2 7 1+ u 7 3 1+ u 7 3 7 3 7 =

89

 3    ( tgx )  + C = 7 arctg  3x  + C arctg  7 3 7 3  7   7  7

t

     

2

=

7 3 dt =

=u = 7 3

du

148. cos x = t 3 2 2 2 ∫ sin xdx = ∫ sin x ⋅ sin xdx = ∫ 1 − cos x ⋅ sin xdx = − sin xdx = dt = − ∫ 1 − t dt = sin xdx = −dt

(

= −t +

)

(

t3 x + C = − cos x + cos 3 + C 3 3

149.

∫ cos

2

)

xdx = ∫ cos x ⋅ cos xdx =

cos x = u − sin xdx = du

(

dv = cos xdx = v = sin x

[∫ cos

2

]

xdx = I =

)

= cos x ⋅ sin x + ∫ sin 2 xdx = sin x cos x + ∫ 1 − cos 2 x dx = sin x cos x + x − ∫ cos 2 xdx = I = sin x ⋅ cos x + x − I 2 I = sin x ⋅ cos x + x sin x ⋅ cos x + x I= +C 2

150.

sin ( α + β ) = sin α cos β + cos α sin β sin ( α − β ) = sin α cos β − cos α sin β sin ( α + β ) − sin ( α − β ) = 2 sin α cos β 1 ∫ sin 3x cos 3xdx = ∫ 2 ( sin 11x + sin ( − 5x ) ) dx =   11x = t    dt 1 −1 cos 11x sin 11xdx = 11dx = dt  = ∫ sin t = ∫ sin tdt = cos t = 11 11 11 11  dt  dx =  11   = =   − 5 x = t    1 1 1  dt  ∫ sin ( − 5x ) dx = − 5dx = dt  = ∫ sin t ⋅  − 5  = − 5 ∫ sin tdt = 5 cos t = 5 cos( − 5x )  dt  dx =  −5   =

1  − cos11x cos 5 x  +  +C 2  11 5 

151.

∫ sin 3x sin ( 5x − 1) dx

cos( α + β ) = cos α cos β − sin α sin β cos( α − β ) = cos α cos β + sin α sin β

cos( α − β ) − cos( α + β ) = 2 sin α sin β sin α sin β =

90

1 ⋅ [ cos( α − β ) − cos( α + β ) ] 2

1

1

∫ sin 3x sin( 5 x − 1) dx = 2 ∫ [ cos( 3x − 5 x + 1) − cos( 3x + 5x − 1) ]dx = 2 ∫ [ cos(1 − 2 x ) − cos( 8 x − 1) ]dx =   1 − 2 x = t    1 1 1  dt  ∫ cos(1 − 2 x ) dx = − 2dx = dt  = ∫ cos t ⋅  − 2  = − 2 ∫ cos tdt = − 2 sin t = − 2 sin (1 − 2 x )  dt  dx = −  2   = =   8 x − 1 = t    dt 1 1 1 ∫ cos( 8x − 1) dx = 8dx = dt  = ∫ cos t 8 = 8 ∫ cos tdt = 8 sin t = 8 sin ( 8x − 1)  dt  dx =  8   =

1 1 1 1 1  − sin (1 − 2 x ) − sin ( 8 x − 1)  + C = − sin (1 − 2 x ) − sin ( 8 x − 1) + C  2 2 8 4 16 

152. cos x = t dx sin xdx sin xdx dt ∫ sin x cos 2 x = ∫ sin 2 x cos 2 x = ∫ 1 − cos 2 x cos 2 x = − sin xdx = dt = −∫ 1 − t 2 t 2 = sin xdx = −dt

(

)

(

1 1 A B Ct + D = = + + = 2 2 2 1−t t (1 − t )(1 + t )t 1 − t 1 + t t2

(

)

(

(

)

(

)

=

A(1 + t ) ⋅ t 2 + B 1 − t 2 ⋅ t 2 + ( Ct + D ) 1 − t 2 ( A + At ) t 2 + ( B − Bt )t 2 + Ct − Ct 2 + D − Dt (1 + t ) = = (1 − t )(1 + t ) t 2 (1 − t )(1 + t )t 2

=

At 2 + At 3 + Bt 2 − Bt 3 + Ct + Ct 2 − Ct 2 − Ct 3 + D + Dt − Dt − Dt 2 = (1 − t )(1 + t )t 2

=

t 3 ( A − B − C ) + t 2 ( A + B − D ) + Ct + D (1 − t )(1 + t ) t 2

= A − B −C = 0 A+B−D =0 C =0 D =1 1 1 1 = 2 + 2 + 2 1−t 1+ t t

= −∫

91

)

)

dt 1−t2 t2

(

)

2A − C − D = 0

A=

1 2

B=

1 2

2 A −1 = 0

1  1     1 1 1 t −2+1  2 2 +C = = −∫  + + 2 dt = − − ln 1 − t + ln 1 + t +  2 2 − 2 + 1 1 − t 1 + t t       

=

=

1 1 1 1 1 − cos x 1 1 − cos x 1 ln 1 − cos x − ln 1 + cos x + + C = ln + + C = ln + +C 2 2 cos x 2 1 + cos x cos x 1 + cox cos x

x y ln x + ln y = ln x ⋅ y ln x − ln y = ln

1

∫ cos nxdx = n sin nx + C

1

1 ln x = ln x 2 = ln x 2 ln x n = n ⋅ ln x

153.

2

(

)

1 + cos 2 x 1  1 + cos 2 x  2 ∫ cos xdx = cos x = 2 = ∫  2  dx = 4 ∫ 1 + 2 cos 2 x + ( cos 2 x ) dx = 4

2

  2 x = t    1 + cos 4 x 1  1 + cos 4 x  dt 1 cos 2 2 x = = ∫ 1 + 2 cos 2 x + dx = ∫ cos 2 xdx = 2dx = dt  = ∫ cos t = sin t =  2 4  2 2 2   dt  dx =  2   =

1  1 1 1 1 3 1 1  ⋅  x + 2 ⋅ sin 2 x + x + ⋅ sin 4 x  + C = x + sin 2 x + sin 4 x + C 4  2 2 2 4 8 4 32 

154.

∫x

dx x2 −1

=

1 =t x 1 x= t dx = −

1

dt t −2 1 1− t2 x2 −1 = 2 −1 = t t2

(

= − arcsin

)

− dt − dt 2 dt t t2 =∫ =∫ = −∫ = − arcsin t + C 1 1− t2 1 1− t2 1− t2 ⋅ ⋅ t t t t2

1 +C x

155. 1 2t + 1 x = 2+ = t t 2 1 4t + 4t + 1 − dt t= x2 = 2 x−2 t dx t2 =∫ = ∫ x − 2 x 2 − 6x + 1 = 2 2 − dt 4t + 4t + 1 12t + 6 2 1 1 − 2 t − 7 t dx = 2 x − 6x + 1 = − +1 = ⋅ t t t2 t t2 2 2 2 2 4t + 4t + 1 − 12t + 6t + t 1 − 2t − 7t = = 2 t t2 x−2=

92

1 t

dt dt dt dt t2 = −∫ = −∫ = −∫ = −∫ =  2 2  1 1 − 2t − 7t 2 1 − 2t − 7t 2 1 − 2t + 7t 2 1 − 7 t + t  ⋅ 7  t t  dt dt dt dt = −∫ = −∫ = −∫ = −∫ 2 2  1  2 1    1 2 1 8  1  1  t +  1 − 7 t +  + − 7 t +  1 − 7 ⋅  t +  −  7 7 8  7 49   7  7  7  1− 8 7   49 

(

1

=−

⋅∫

8 7

7

=−

8 ⋅ 7 ∫



8

 1 t + dt = 7 =u 2  8  1  7  t +   7   1−  8     7 

 arcsin 7 

1

=−

dt

)

= du

8 7

      

=

 8  dt = du  = 7  

   1 1 t + 1   +  du 1 7  + C = − 1 arcsin x − 2 7  + C = =− arcsin    7 8  7 8 1− u2     7  7    7+ x−2  1 x+5 +C = − arcsin +C 8 ⋅ ( x − 2 )  7 8 ⋅ ( x − 2)

156.

∫ x⋅(

dx x + 5 x2

x = t 10

10t 9 dt

) = dx = 10t dt = ∫ t ( t 9

10

10

+ 5 t 20

)

10t 9 dt 10t 9 dt dt = ∫ 10 5 4 = ∫ 9 = 10 ∫ 5 = 4 t t +t t ⋅ t ⋅ t ( t + 1) t ( t + 1)

(

)

1 At 4 + Bt 3 + Ct 2 + Dt + E F = + = 5 5 ( t + 1) t ( t + 1) t =

( At

4

)

+ Bt 3 + Ct 2 + Dt + E ⋅ ( t + 1) + t 5 F At 5 + At 4 + Bt 4 + Bt 3 + Ct 3 + Ct 2 + Dt 2 + Dt + Et + Ft 5 = = t 5 ( t + 1) t 5 ( t + 1)

t 5 ( A + F ) + t 4 ( A + B) + t 3 ( B + C ) + t 2 ( C + D) + t( D + E ) + E = = t 5 ( t + 1) E =1 D+E =0 C+D=0 B+C =0 A+ B = 0 A+ F = 0 D = −1 C =1 B = −1 A =1 F = −1 =

 t4 − t3 + t2 − t +1 1  1  dt = 10 ∫  t −1 − t − 2 + t −3 − t − 4 + t −5 − = 10∫  − dt = 5  t + 1 t + 1 t    

93

t −2+1 t −3+1 t −4+1 t −5+1 = 10 ln t − 10 + 10 + 10 − 10 − ln t + 1 + C = − 2 +1 − 3 +1 − 4 +1 − 5 +1 10  x 1 1 1 1  = 10ln 10 + 10 − 5 + − +C x +1 x 2 x 310 x 3 45 x 2  

157. x = 3 sin t dx = 3 cos tdt dx 3 cos tdt cos tdt cos tdt x =∫ = 3∫ = 3∫ = ∫ 3 − x 2 = sin t = 3 3 − 3 sin 2 t 3 1 − sin 2 t 3 1 − sin 2 t x t = arcsin 3 cos tdt x =∫ = ∫ dt = t = arcsin +C 3 cos 2 t

(

)

158. 1 ( 2 sin x cos x ) 2 cos 2 xdx = 4 1 1 1  sin 2 x sin 2 2 x ⋅ cos 2 x   1 + cos 2 x  1 1  2 dx = = ∫ ( sin 2 x ) 2 ⋅  + dx = ∫ sin 2 x ⋅  + cos 2 x dx = ∫   4 2 4 4  2 2   2 2   1 1 1 − cos 4 x 1 = ∫ sin 2 2 x + sin 2 x cos 2 x dx = ∫ dx + ∫ sin 2 2 x cos 2 xdx = 8 8 2 8 3 1 1 1 1  1 sin 2 x 2 = ∫ (1 − cos 4 x ) dx + ∫ sin 2 x cos 2 xdx =  x − sin 4 x  + ⋅ +C 16 8 16  4 6  8

∫ sin

2

x cos 4 xdx = ∫ ( sin x cos x ) 2 cos 2 xdx = ∫

(

)

  4 x = t    1 1 ∫ cos 4 xdx = 4dx = dt  = 4 ∫ cos tdt = 4 sin 4 x  dt  dx =   4  sin 2 x = t  1 2 1 1 t 3 t 3 sin 3 2 2 sin 2 x cos 2 xdx = = t dt = ⋅ = = 2 cos 2 xdx = dt  2 ∫ 2∫ 2 3 6 6   =

x sin 4 x sin 3 2 x − + +C 16 64 48

Određeni integrali 94

Integralna suma za funkciju y = f ( x ) na intervalu [ a, b] i podjeli n

a = x0 < x1 < ⋅ ⋅ ⋅ < x n = b tog intervala je

∑f (ξ )∆xi

.

i =1

xi −1 ≤ ξ i ≤ xi , ∆xi = xi − xi −1 , i = 1,2,3,..., n b

n

lim ∑ f ( ξ i )∆xi = ∫ f ( x ) dx = Px

max ∆xi →0 i =1

a

Γf f ( ξ2 ) b

∫ f ( x ) dx

a

a

b

Osobine određenih integrala a

∫ f ( x ) dx = 0 a

ako je funkcija neparna. ako je funkcija parna funkcija. Newton-Leibnitz-ova formula

Funkcija f ( x ) neprekidna na [ a, b] i ϕ ( x ) njena primitivna funkcija tj. ϕ ( x ) = f ( x ) b

tada je

∫ f ( x ) dx = ϕ ( x ) a

159. 95

b a

= ϕ( b) − ϕ( a) .

4

x2 xdx = ∫ 2 0

4

42 02 − =8 2 2

= 0

160. 1

x n +1 ∫ x dx = n + 1 0

1n +1 0 n +1 1 = − = n +1 n +1 n +1

1

n

0

161. 0

3x 4 + 3x 2 + 1 dx = x2 +1

∫π



3x 4 + 3x 2 + 1 1  x3  2 3 ∫ x 2 + 1 dx = ∫  3x + x 2 + 1 dx = 3 3 + arctgx = x + arctgx =

4

(

= x 3 + arctgx

)

0 −

π 4

3

π  π  π π = 0 + 0 −  −  + arctg  −  = + arctg 4  4  4  64 3

162.

A B A( x − 1) + B( x + 2 ) Ax − A + Bx + 2 B + = = = ( x + 2)( x − 1) ( x + 2)( x − 1) x + x − 2 x + 2 x −1 x( A + B ) − A + 2 B = A+ B = 0 ( x + 2)( x − 1) +∞ dx − A + 2B = 1 = ∫ x2 + x − 2 = 2 3B = 1 1 1 B= A=− 3 3 1

2



=

1 1      3 + 3 dx =  − 1 ln x + 2 + 1 ln x − 1  =  ln 3 x − 1   3 x + 2   x + 2 x −1  3      

+∞ 

∫ 2

=



+∞

=

2

2

− 1 2 = − ln 3 = − ln 2 3 = ln 2 4 3

163. y = 4x ⇒ y = 2 x 4 4 y = x+ 5 5 Presjek funkcija f1 i f2 y 2 = 4x 4 4 y = x+ 5 5 2

4 4  x +  = 4x 5 5

96

( f1 ) ∩ ( f 2 ) je rješenje sistema jednačina.

2

(

)

4 2   x + 1 = 4x 5 16 2 25 x + 2x + 1 = 4x ⋅ 25 4 2 4 x + 8 x + 4 = 25 x

(

)

4 x 2 − 17 x + 4 = 0 17 ± 289 − 64 8 17 ± 225 17 ± 15 x1, 2 = = 8 8 2 1 x1 = = 8 4 32 x2 = =4 8 x1, 2 =

3     4 2 2 4x 4  x 4 x 4  4 3 2 2 4   P = ∫2 x − − dx = 2 ⋅ − ⋅ − x = x − x − x 3 5 2 5  1 3 5 5 5 5   1   4 4 2   4 2 4  4 1 2 1 4 1   32 32 16 1 1 1 =  ⋅ 8 − ⋅ 16 − ⋅ 4 −  ⋅ − ⋅ − ⋅   = − − − + + = 5 5 5 5 6 40 5  3 8 5 16 5 4   3 3 4

=

1280 − 768 − 384 − 20 + 3 + 24 135 27 9 = = = 120 120 24 8

164. y 2 = 2x + 1 x − y −1 = 0

( 4,3)

x = y +1 y 2 = 2( y + 1) + 1 y2 = 2y + 2 +1 y2 − 2y − 3 = 0 y1 = −1 y2 = 3 x = y +1 x1 = −1 + 1 = 0 x2 = 3 + 1 = 4

97

 1   − ,0   2 

P∆

4 1 4

=

0

P=2∫

1 − 2

 = 2  

1

4

1 2 x + 1dx + + ∫ 2 x + 1dx + ∫ 2 0 1

( 2 x + 1) 3   

3

0 1 − 2

+

1  + 2  

(

)

2 x + 1 − ( x − 1) dx =

( 2 x + 1) 3   

3

 +  0 

1

( 2 x + 1) 3   

3

 x2 −  1  2 4

   

4

+x

1

4

=

1

1 2 1 1 1 16 1  1  3 3 1 27 3 3   = 2 ⋅  − 0  + +  − + − − 8 − + 4 − 1 = + − + 1 + + 3 =   3 3 3   2 3 2 3 2 3 3  2  3

165. x2 2 1 y= 1+ x2 x2 = 2y 1 y= 1+ 2y y=

2y2 + y −1 = 0

y

y=

x2 2

(1,0)

y=

1 1+ x2

0

−1± 1+ 8 −1± 3 = 4 4 y1 = −1 y1, 2 =

x

1 2 = −2 ∈ R

y2 = x1, 2

x3, 4 = ±1 1  1 x2 P = ∫  − 2 2 −1 1 + x π 1 3π − 2 = − = 2 3 6

 1 x3 dx = arctgx − ⋅  2 3 

1 −1

= arctg1 −

1  1 1 −  arctg ( − 1) +  = 2arctg1 − = 6  6 3

166. Odrediti zapreminu V koja nastaje rotacijom prave y = y

y=

1 1+ x2 y=0

x= − 1 98

x=1

1 oko x – ose. 1+ x2

1+ x2 − x2

1+ x2 x 2 dx dx − ∫ 1+ x2 2 ∫ 1+ x2 2 = 1+ x2 dx x xdx =∫ − ∫x⋅ dx = arctgx − ∫ x ⋅ 2 2 1+ x 1+ x 1+ x2

(

1

2

1

 1  V = π ∫ y 2 dx = π ∫  dx = 2  1 + x   −1 −1

)

dx = ∫

(

(

)

(

)

)

(

)

2

=

x 1 1 x = arctgx + − arctgx = arctgx + 2 2 2 2 1+ x 2 1+ x2 xdx ∫ x ⋅ 1 + x 2 2 =I1

(

(

)

(

=

)

)

  xdx ′ x=u = v   1+ x2       2 1+ x = t   xdx  I1 = x ⋅ xdx = dx = du v=∫ = 2 xdx = dt = ∫ 2 2 2 2   1 + x 1 + x = dt = xdx =   2   1 dt 1 t − 2+1 1 1   v= ∫ 2 = ⋅ =− =− 2   2 t 2 − 2 +1 2t 2 1+ x   −x 1 x 1   +∫ dx = − + arctgx =  2 2 2 2 2 1+ x 21+ x  2 1+ x  1  1  1 x 1  1 1  1  = π ⋅  arctgx + = π ⋅  arctg1 +  −  arctg ( − 1) −  = π  arctg1 +  = 2  2⋅2  2 2 ⋅ 2  2 2 1 + x  −1   2 2

(

(

)

)

(

)

(

(

)

(

(

)

(

)

)

2 π π 2 + 2π π 1 π = π ⋅ +  = + = 2 4  4 2 4

Diferencijalne jednačine 99

)

Diferencijalne jednačine prvog reda y = y ( x ) , y ′ = f ( x, y ) . Oblik jednačine je y ′ = f ( x, y ) Tipovi diferencijalnih jednačina 1.) Jednačina koja razdvaja promjenljive f ( x ) dx = F( y ) dy rješenje : ∫ f ( x ) dx = ∫ F( y ) dy + C . 2.) Homogena diferencijalna jednačina y ′ = ϕ y    x

 y x

pomoću smjene   = z

y = x⋅z

y ′ = z + x ⋅ z ′ rješenje jednačine.

3.)Linearna diferencijalna jednačina y′ + f ( x) y = g ( x) f ( x ) , g ( x ) - neprekidne funkcije − f ( x ) dx  f dx ⋅ ∫ ∫ ( x ) ⋅ g ( x ) dx + C  rješenje : y =  ∫  



 dx

ako je linearna diferencijalna jednačina data u obliku dy + f ( y ) ⋅ x = g ( y ) − f ( y ) dy  f dy ⋅ ∫ ∫ ( y ) ⋅ g ( y ) dy + C  . tada je rješenje : x =  ∫  





3.) Bernulijeva diferencijalna jednačina y′ + f( x) y = g ( x) ⋅ y n y′ z′ = yn 1− n ydx − xdy = 0 ydx = xdy dx dy = x y ∫ dx dy ∫ x =∫ y ln x = ln y + C ln

(

100

)

xy + x ⋅ y ′ = y x

(

)

y +1 ⋅

)

y′ =

dy =y dx

y + 1 dy dx = y x

1 y

n −1

= z z ′ = (1 − n )

z′ + f ( x ) z ′ = g ( x ) linearna diferencijalna jednačina 1− n

x =C y

167.

(

( n ≠ 0 ∧ n ≠ 1) uvodi se smjena



dy dx

y′ yn



(

)

y + 1 dy dx =∫ y x

1  1 − 1   ∫  y + y dy = ∫ x 2 dx   1  −1+1   y2  x − 2 +1  + ln y  = +C  − 1 +1  − 1 +1   2  2  1

y2 + ln y = 2 x + C 1 2 2 y + ln y = 2 x + C

168.

169.

y ⋅ y′ + x = 1 dy y⋅ + x =1 dx dy y⋅ = 1− x dx

y ⋅ dy = (1 − x ) dx

(

dy = x dx x  dx ydy = 2 1 + x ∫

(

)

x

 dx



∫ ydy = ∫ 2(1 + x )

∫ ydy = ∫ (1 − x ) dx 2

)

2 ⋅ 1 + x y ⋅

y2 1 = ⋅ ln 1 + x + C ⋅ 2 2 2

2

y x = x− +C ⋅2 2 2 y 2 = 2x − x 2 + C

y 2 = ln 1 + x + C

170.

y − xy ′ − yy ′ = x y − x = y ′( x + y ) y−x = y′ y+x y−x :x y′ = y+x :x y −1 y′ = x y +1 x z −1 z + xz ′ = z +1 dz z − 1 z+x = ⋅ ( z + 1) dx z + 1 ( z + 1)( z + xz ′) = z − 1

101

y =x x

y = xz

y ′ = z + xz ′

z 2 + xz ′ ⋅ z + z + x ⋅ z ′ − z = −1 z ′x( z + 1) + z 2 = −1 −1− z2 1+ z dz − 1 − z 2 x⋅ = dx z +1 ( z + 1) dz = dx x −1− z2 ( z + 1) dz = dx − x ∫ 1+ z2 ( z + 1) dz = dx −∫ ∫x 1+ z2 1  −  ln 1 + z 2 + arctgz  = ln x + C 2  xz ′ =

1 y2  y  −  ln 1 + 2 + arctg    = ln x + C 2 x  x    1 y2  y − ln 1 + 2 − arctg   = ln x + C 2 x  x y 1 x2 + y2 − arctg = ln x ⋅ C + ln x 2 x2 − arctg

y x2 + y2 = ln C ⋅ x + ln x x2

− arctg

y = ln C ⋅ x 2 + y 2 x

171.

x y′ = y x +1 x( x + 1) = y ⋅ y ′ dy x( x + 1) = y dx x ⋅ ( x + 1) dx = ydy

∫ (x

2

)

+ x dx = ∫ ydy

x3 x2 y 2 + = + C ⋅6 3 2 2 2 x 3 + 3x 2 = 3 y 2 + C

102

  1 + z 2 = t    1 dt 1 z ∫ 1 + z 2 dz = 2 zdz = dt  = 2 ∫ t = 2 ln z  dt   zdz =   2  1 = ln 1 + z 2 2

172.

7 x + xy + y ′( y + xy ) = 0 7 − −1 dy y = 1 dx +1 x dy dx = 7 1 − −1 +1 y x dy dx = − 7 − y 1+ x y x ydy xdx = − 7 − y 1+ x ∫ ydy xdx ∫ − 7 − y = ∫1+ x y+7−7 x +1−1 −∫ dy = ∫ dx 7+ y 1+ x  y+7  7 dx −  ∫ dy + ∫ dy  = ∫ dx − ∫ 7+ y  1+ x  7+ y − y + 7 ln 7 + y = x − ln 1 + x + C

174. x 2 + y 2 = 2 xyy ′ y′ =

x2 + y2 / : x2 2 xy / : x 2

y2 1+ 2 x ′ y = y 2 x 1+ z2 z + xz ′ = 2z 2 1+ z xz ′ = −z 2z 1 + z 2 − 2z 2 xz ′ = 2z dz 1 − z 2 x = dx 2z

103

y =z x

y′ = z + x ⋅ z′

173.

xy ′ − y = xy ′ =

x2 +y2

x2 +y2 +y

y′ = 1 +

y2 x

2

+

y x

y = z y ′ = z + xz ′ x

z + xz ′ = 1 + z 2 + z xz ′ = 1 + z 2 xdz = 1 +z 2 dx dz dx = x 1 +z 2



dz 1 +z

2

=∫

∫ dx x

ln z + 1 + z 2 = ln x +ln C ln

y y2 + 1 + 2 = ln C ⋅ x x x

y y2 + 1 + 2 =C ⋅ x x x y+

y 2 +x 2 =C ⋅ x x

y+

x 2 + y 2 =C ⋅ x 2

175.

− 2 zdz dx −∫ =∫ 2 x 1− z

y + y ′ = x − dx dx y =  ∫ ⋅ ∫ ∫ ⋅ x dx +C     

y2 ln x + ln C + ln 1 − 2 = 0 x ln x ⋅ C ln  1=

2

x −y x2

2

x

y = −x ⋅

=0

x ⋅ C x2 − y2

= 0

2

y

C ⋅ x2 − y2 x 2

x = C ⋅ x − y2

y y y

176.

ln 1 − y

−1

3 C1 = x 1− y 3

− x3

y = 1 − C1 ⋅ 

y = 1 + C ⋅ − x

104

3

⋅ x dx +C

[

]

g ( x ) = x

f( x) = 1

− dx dx y =  ∫  C + ∫ ∫ ⋅ x dx   

(

3

y = − x C + ∫ 2 x dx

)

1   y = − x  C + 2 x  2  

pošto je y= 1 , za x=0 imamo 1=C +

C1 ⋅ − x = 1 − y

x

]

    2 x =t   2x  ∫  dx = 2dx = dt =  = −x ⋅ ∫ 2 x dx +C  dt dx =   2   1  1 2x t  ∫  dt =   2 2  1  = −x ⋅  2 x +C  2  1 C = x + x 2  x  C = + x 2 

y ′ + y = x

x3 +C 3

= ln x

[∫

177.

y ′ + 3 x 2 y = 3x 2 dy = 3 x 2 (1 − y ) dx dy = 3 x 2 dx ∫ 1− y − ln 1 − y = 3

g ( x ) = x

f ( x ) =1

− ln 1 − z 2 = ln x + C

1 2

tj.

C=

1 2

traženo partikularno rješenje je x − − x y= 2

178. y′ + 2 y = x 2 + 2x g( x) = x 2 + 2x

f( x) = 2

− f dx f dx y =  ∫ ( x ) ∫ ( x ) ⋅ g ( x ) dx + C   

(

)

− 2 dx  − 2 dx y = ∫ ⋅ ∫ ∫ ⋅ x 2 + x dx + C   

[

(

)

y = −2 x ⋅ ∫ 2 x ⋅ x 2 + x dx + C

]

 x 2 2 x x2 x 32 x  y = −2 x ⋅  + − + C  2 4  2 

(

)

 y = 2 x x 2 + 2 x dx = x 2 2 x dx + 2 x2 x dx =  ∫ ∫ ∫   2 2 x   x = u  dx = v ′   2 2x   1 2x  =  ∫ x  dx =   2 xdx = u ′ v =      2    2x     ′ x = u  dx = v 2 2x  = x  − 2 x xdx =  =  1 2x  ∫    2 dx = du v =    2     2 2x 2 2x x 2 2 x x2 x 2 x 1 2x  2x = = x  − x  + 1 2 x = − − + x −    2 2 4 2 2 4 2   x = u 2 x dx = v ′    =  ∫ 2 x2 x dx = 2 ∫ x2 x dx =   dx = du v = 1 2 x      2     2 x    = 2 ⋅  x − 1 2 x dx  = x ⋅ 2 x − 1 2 x  ∫  2    2 2      

179. y ′ cos x = y sin x + cos 2 x y ′ cos x − y sin x = cos 2 x / : cos x sin x y′ − y = cos x cos x y ′ − tgx ⋅ y = cos x f ( x ) = −tgx

g ( x ) = cos x

− f dx f dx y =  ∫ ( x ) ⋅  ∫ ∫ ( x ) ⋅ g ( x ) dx + C    tgxdx  − tgxdx y = ∫ ⋅ ∫  ∫ ⋅ cos xdx + C   

cos x = t  sin x dt   ∫ tgxdx = ∫ cos x dx = − sin xdx = dt  = −∫ t = − ln t = − ln cos sin xdx = − dt 

105

− ln cos x

y=

[

⋅ ∫

⋅ cos xdx + C

[

−1

ln cos x

y=

ln cos x

⋅ ∫ cos x ⋅ cos xdx + C

[

]

]

]

1 ⋅ ∫ cos 2 xdx + C cos x 1  1 + cos 2 x  y= ⋅ ∫ dx + C  cos x  2  y=

1 1 1  ⋅  x + sin 2 x + C  cos x  2 4  x sin 2 x y= + +C 2 cos x 4 cos x y=

180. xdy − 2 ydx = x 3 ln xdx / : dx dy x − 2 y = x 3 ln x dx x ⋅ y ′ − 2 y = x 3 ln x / : x 2 y ′ = y = x 2 ln x x 2 f( x) = − , g ( x ) = x 2 ln x x − f dx f dx u = ln x y =  ∫ ( x ) ⋅  ∫ ∫ ( x ) ⋅ g ( x ) dx + C    ln xdx = 1 ∫ u ′ = dx 2 2   − ∫ dx x ∫ dx y =  x ⋅  ∫  x ⋅ x 2 ln xdx + C   

(

)

[

y = 2 ln x ⋅ ∫ −2 ln x ⋅ x 2 ln xdx + C 2

[

−2

y = ln x ⋅ ∫ ln x ⋅ x 2 ln xdx + C

[ ⋅ [ ∫ ln xdx + C ]

y = x 2 ⋅ ∫ x − 2 ⋅ x 2 ln xdx + C y = x2

]

]

dx = v ′ v=x

= x ln x − ∫ dx = x ln x − x

]

y = x 2 ⋅ [ x ln x − x + C ]

181.

Konstanta za drugi izvod r 2

y ′′ − a y =  2

bx

r 2 − a2 = 0 polinom od r r1 = − a r2 = a

( p( r ) )

y 0 = C1 ⋅ − ax + C 2 ⋅ ax

η=

bx bx = 2 p( b ) b − a 2 − ax

y = y 0 + η = C1 ⋅  106

bx + C2 ⋅  + 2 b − a2 ax

182.

183.

y ′′ − 2 y ′ + y = 2 x

y ′′ − 3 y ′ + 2 y = 2 x x 2 + x

2

p : r − 2r + 1 = 0 r1, 2 = 1 1x

(

)

2

r − 3r + 2 = 0 1x

y 0 = C1 ⋅  + x ⋅ C 2 ⋅  b=2 p( b ) = p( 2) p( 2) = 2 2 − 2 ⋅ 2 + 1 = 1 2 x 2 x η= = = 2 x p( 2) 1

3± 9− 4⋅2 r1 = 1 r2 = 2 b = 2 2 Kada je b jednako sa jednim r1 ili r2 tada je η = x ⋅ ( a 0 + a1 x ) ⋅ 2 x r1, 2 =

y 0 = C1 ⋅ r1x + C 2 ⋅ r2 x y 0 = C1 ⋅ x + C 2 ⋅ 2 x

y = y 0 + η = C1 ⋅ x + x ⋅ C 2 ⋅ x + 2 x

184.

y +1 y′ = x dy y + 1 = dx x dy dx = y +1 x

ln y + 1 = ln x + ln C y +1 = C ⋅ x y = Cx − 1

y 1 = x x 1 1 y′ − ⋅ y = x x 1 1 f( x) = − g( x) = x x dx  1  − ∫ dx 1 ∫ y =  x ⋅  ∫  x ⋅ dx + C  x   −1 1   y = ln x ⋅  ∫ ln x ⋅ dx + C  x    1 1  y = x ⋅  ∫ ⋅ ⋅ dx + C   x x  y′ −

[

y = x ⋅ ∫ x − 2 dx + C  1  y = x ⋅ − + C   x  y = Cx − 1

107

]

Sadržaj stranica Funkcija – definicija ................................................................................ 3 Granične vrijednosti – ( limesi) .............................................................. 10 Granične vrijednosti funkcije ................................................................. 29 Diferencijalni račun ................................................................................. 35 Izvod .......................................................................................................... 36 Izvod složenih funkcija ............................................................................ 37 Funkcije .................................................................................................... 40 Integrali .................................................................................................... 75 Parcijalna integracija .............................................................................. 85 Određeni integrali ................................................................................... 95 Newton – Leibnitz-ova formula ............................................................. 95 Diferencijalne jednačine ......................................................................... 100 Sadržaj ..................................................................................................... 108

108

Related Documents