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(B) To find the matrix of cofactors,we calculate the cofactor $A_{ij}$ for each element $a_{ij}$ using the formula $A_{ij} = (-1)^{i+j} M_{ij}$,where

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$\left[\begin{array}{ccc}0 & -8 & 4 \ -1 & 3 & -2 \ 1 & -7 & 2\end{array}ight]$

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(B) To find the matrix of cofactors,we calculate the cofactor $A_{ij}$ for each element $a_{ij}$ using the formula $A_{ij} = (-1)^{i+j} M_{ij}$,where $M_{ij}$ is the minor of the element $a_{ij}$.$A_{11} = (-1)^{1+1} \begin{vmatrix} 1 & 2 \ 1 & 2 \end{vmatrix} = (1)(2-2) = 0$$A_{12} = (-1)^{1+2} \begin{vmatrix} 3 & 2 \ -1 & 2 \end{vmatrix} = (-1)(6 - (-2)) = -8$$A_{13} = (-1)^{1+3} \begin{vmatrix} 3 & 1 \ -1 & 1 \end{vmatrix} = (1)(3 - (-1)) = 4$$A_{21} = (-1)^{2+1} \begin{vmatrix} 0 & -1 \ 1 & 2 \end{vmatrix} = (-1)(0 - (-1)) = -1$$A_{22} = (-1)^{2+2} \begin{vmatrix} 2 & -1 \ -1 & 2 \end{vmatrix} = (1)(4 - 1) = 3$$A_{23} = (-1)^{2+3} \begin{vmatrix} 2 & 0 \ -1 & 1 \end{vmatrix} = (-1)(2 - 0) = -2$$A_{31} = (-1)^{3+1} \begin{vmatrix} 0 & -1 \ 1 & 2 \end{vmatrix} = (1)(0 - (-1)) = 1$$A_{32} = (-1)^{3+2} \begin{vmatrix} 2 & -1 \ 3 & 2 \end{vmatrix} = (-1)(4 - (-3)) = -7$$A_{33} = (-1)^{3+3} \begin{vmatrix} 2 & 0 \ 3 & 1 \end{vmatrix} = (1)(2 - 0) = 2$Thus,the matrix of cofactors is $\left[\begin{array}{ccc}0 & -8 & 4 \ -1 & 3 & -2 \ 1 & -7 & 2\end{array}ight]$.

For the matrix $A=\left[\begin{array}{ccc}2 & 0 & -1 \\ 3 & 1 & 2 \\ -1 & 1 & 2\end{array}\right]$,the matrix of cofactors is

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