Let A= [α, -1; 6, β], α>0, such that det (A)=0 and α+β=1. If I denotes 2 × 2 identity matrix, then the matrix ( I + A )^8 is:

Let $\displaystyle A=\left[\begin{array}{cc}\alpha & -1 \\ 6 & \beta\end{array}\right], \alpha>0$, such that $\displaystyle \operatorname{det}(A)=0$ and $\displaystyle \alpha+\beta=1$. If I denotes $\displaystyle 2 \times 2$ identity matrix, then the matrix $\displaystyle (\mathrm{I}+\mathrm{A})^8$ is :