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Question
If \[A = \begin{bmatrix}5 & 3 & 8 \\ 2 & 0 & 1 \\ 1 & 2 & 3\end{bmatrix}\]. Write the cofactor of the element a32.
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Solution
Minor of a32 = M32 = \[\begin{vmatrix}5 & 8 \\ 2 & 1\end{vmatrix} = 5 - 16 = - 11\]
Cofactor of a32 = A32 = (−1)3+2 M32 = 11
Hence, the cofactor of the element a32 is 11.
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