Question

If \[A = \begin{bmatrix}5 & 3 & 8 \\ 2 & 0 & 1 \\ 1 & 2 & 3\end{bmatrix}\]. Write the cofactor of the element a₃₂.

Answer 1

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.