TUGAS4 MIK106 ALJABAR LINIER AGUNG PRATAMA (NIM: 20170310028)
Diketahui matriks: 3 1 2 𝐴 = [1 −2 −9] 4 3 1 Tentukan: a. Minor b. Kofaktor c. Adjoin JAWAB a. Minor DIKALI
−2 −9 M11 = | | -2 – (-27) = 25 3 1 1 −9 M12 = | | 1 – (-36) = 37 4 1 1 −2 M13 = | | 3 – (-8) = 11 4 3 1 3 M21 = | | 1 – 6 = -5 2 1 3 M22 = | 4
2 | 3 – 8 = -5 1
3 M23 = | 4
1 |9–4=5 3
1 2 M31 = | | -9 – (-4) = -5 −2 −9 3 2 M32 = | | -27 – 3 = -30 1 −9 3 1 M33 = | | -6 – 1 = -7 1 −2
b. Kofaktor C11 = + |
−2 −9 | + (-2 – (-27)) = 25 3 1
1 C12 = - | 4 C13 = + |
−9 | - (1 – (-36)) = -37 1
1 −2 | + (3 – (-8)) = 11 4 3
1 C21 = - | 2
3 | - (1 – 6) = 5 1
3 C22 = + | 4
2 | + (3 – 8) = -5 1
C23 = - |
3 1 | - (9 – 4) = -5 4 3
C31 = + |
1 2 | + (-9 – (-4)) = -5 −2 −9
3 C32 = - | 1 C33 = + |
2 | - (-27 – 3) = 30 −9
3 1 | + (-6 – 1) = -7 1 −2
Maka, Matriks Kofaktornya : 25 −37 11 C=| 5 −5 −5| −5 30 −7
c. Adjoin 25 5 −5 CT = |−37 −5 30 | 11 −5 −7