Answer
See below
Work Step by Step
We are given:
$A=\begin{bmatrix}
-2 & 9 & 0 & -1\\4 &-6 & 8 &8\\0& -1 & -3 & 4\\7 & -7&3&1
\end{bmatrix}$
The minors are:
$M_{41}=\begin{vmatrix}
9 & 0 & -1\\-6 & 8 &8\\ -1 & -3 & 4
\end{vmatrix}=478$
$M_{22}=\begin{vmatrix}
-2 & 0 & -1\\0& -1 & 4\\7 & -7&1
\end{vmatrix}=9$
$M_{23}=\begin{vmatrix}
-2 & 9 & -1\\0& -1 & 4\\7 & -7&1
\end{vmatrix}=191$
$M_{43}=\begin{vmatrix}
-2 & 9 &-1\\4 &-6 & 8 \\0& -1 & 4
\end{vmatrix}=-108$
The cofactors of the matrix A are:
$C_{41}=(−1)^{4+1}.M_{41}=-478$
$C_{22}=(−1)^{2+2}.M_{22}=9$
$C_{23}=(−1)^{2+3}.M_{23}=-191$
$C_{43}=(−1)^{4+3}.M_{43}=108$
