Derivate f ( x) − f ( x 0 ) ∃ lim = 0 şi este finită. x → x0 x − x0
f(x) are derivată în x0 dacă
1.
xn
2.
f ' ( x) 0 nx n −1 rx r −1 ex a x ln(a ) 1 1 ⋅ ⋅u' 2 u 1 x cos( x) − sin( x)
f (x) ctn (x ≥ 1∈ I )
No.
5.
xr ex ax
6.
u
3. 4.
7.
ln( x )
8. 9.
sin( x) cos( x )
10.
arcsin( x)
11.
arccos( x)
12.
arctg ( x )
13.
arcctg (x )
No.
Operands
Result
1.
( f + g ) ( x)
f ( x ) + g ' ( x)
2.
( fg ) ' ( x)
f ' ( x ) ⋅ g ( x ) + f ( x) ⋅ g ' ( x )
3.
(λ ⋅ f ( x)) '
4.
f ( ) ' ( x) g
λ ⋅ f ' ( x) f ' ( x) ⋅ g ( x ) − f ( x ) ⋅ g ' ( x ) g 2 ( x)
5.
(
f ( x)
f ' ( x)
'
λ ( g f ) ' ( x)
6. Trick:
)'
a = e ln( a ) .
1 1− x2 −1
1− x2 1 1+ x2 −1 1+ x2
∀x ∈ (−1,1)
∀x ∈ (−1,1) ∀x ∈ R ∀x ∈ R
'
λ g ( f ( x)) ⋅ f ' ( x) '
Integrale Nedefinite No.
SpecificaŃii
Integrala nedefinită
f : R → R; 1.
2.
3.
f ( x) = x n ; n ∈ N f : J → R; J ⊂ (0, ∞) f ( x) = x a ; a ∈ R − {1} f :R→ R
n ∫ x dx =
x n +1 +c n +1
a ∫ x dx =
x a +1 +c a +1
ax ∫ a dx = ln(a) + c x
f ( x) = a x ; a ∈ R+* − {1} f : J → R; J ⊂ R *
4.
1 f ( x) = x f : J → R; J ⊂ R − {− a, a}
5.
1 f ( x) = 2 , (a ≠ 0) x − a2 f :R→R 1 f ( x) = 2 ;a ≠ 0 x + a2 f :R→ R f ( x ) = sin( x ) f :R→R f ( x) = cos( x)
6.
7.
8.
9.
1
∫ x dx = ln( x ) + c ∫x
2
∫x
2
1 1 x−a dx = ln +c 2 2a x + a −a
x 1 1 dx = arctg ( ) + c 2 a a +a
∫ sin( x)dx = − cos( x) + c ∫ cos( x)dx = sin( x) + c
π f : J → R; J ⊂ R − (2k + 1) k ∈ Z 2 1 f ( x) = cos 2 ( x )
1
∫ cos
f : J → R; J ⊂ R − {kπ k ∈ Z } 10.
11.
12.
13.
f ( x) =
∫ sin
1 sin 2 ( x)
π f : J → R; J ⊂ R − (2k + 1) k ∈ Z 2 f ( x) = tg ( x )
( x)
1 2
( x)
dx = tg ( x ) + c
dx = −ctg ( x) + c
∫ tg ( x)dx = − ln( cos( x) ) + c
f : J → R; J ⊂ R − {kπ k ∈ Z } f ( x) = ctg ( x) f : J → R; J ⊂ (−a, a), a > 0, 1 f ( x) = a2 − x2
2
∫ ctg ( x)dx = ln( sin( x) ) + c ∫
1
x dx = arcsin( ) + c a a2 − x2
f : R → R; a ≠ 0 1 f ( x) = x2 + a2 f : J → R, J ⊂ (−∞,−a ) sau J ⊂ (a, ∞ ), a > 0, 1 f ( x) = 2 x − a2
14.
15.
∫
∫
1 x +a 2
2
1 x −a 2
2
dx = ln( x + x 2 + a 2 ) + c
dx = ln x + x 2 − a 2 + c
Alte formule:
E x (x + 1) 2
2
2
=
A B Cx + D Fx + G + 2 + 2 + 2 x x x + 1 (x + 1) 2
Se notează:
ax 2 + bx + c = x a + t = xt + c
daca a > 0 daca c > 0
= (x - x 1 )t daca a < 0, c < 0, ∆ = b 2 − 4ac > 0 I.
x tg ( ) = t ⇔ x = 2arctg (t ) = ρ 2 2 ρ'= 1+ t 2 2t 1− t2 2t sin( x ) = , cos( x) = , tg ( x ) = 2 2 1+ t 1+ t 1− t2 II. R(-sin x,
cos x) = R(sin x, cos x) tg ( x) = t ⇒ x = arctg (t ) cos 2 ( x) =
1 t2 t 2 , sin ( ) = , sin( x ) cos( x ) = x 2 2 1+ t 1+ t 1+ t2
R(-sin x, cos x) = R(sin x, cos x) cos( x ) = t ⇒ x = arccos(t )
III.
∫ f ( x) g ' ( x)dx =
fg − ∫ f ' ( x) g ( x )dx