1. Diketahui matriks A, dan I berordo 2 x 2, dan A mempunyai invers jika A² = 9A + 6I dan A³ = pA + tI, maka nilai 6p + 10t =... 2. Diketahui Matriks A

1. [tex]A^{3}=A^{2}*A=(9A+6I)*A=9A^{2}+6AI=9(9A+6I)+6A=81A+54I+6A=87A+54I[/tex]
[tex]p=87, t=54[/tex]
[tex]6p+10t=522+540=1062[/tex]

2. [tex]A^{2}=8A+5I[/tex]
[tex]A=8I+5A^{-1}[/tex]
[tex]A^{-1}=\frac{A}{5}-\frac{8I}{5}[/tex]
[tex]m=\frac{1}{5}, n=-\frac{8}{5}[/tex]
[tex]10m+6k=\frac{10*1}{5}-\frac{6*8}{5}=2-\frac{48}{5}=2-9,6=7,6[/tex]