If Aij is the cofactor of the element aij of the determinant|(2,-3,5)(6,0,4)(1,5,-7)|, then write the value of a32. A32.

Question

If A_ij is the cofactor of the element a_ij of the determinant

 \(\begin{vmatrix} 2 &-3 & 5 \\[0.3em] 6 & 0 & 4\\[0.3em] 1 & 5 &-7 \end{vmatrix}\) , then write the value of a₃₂. A₃₂.

Answer 1

a_32.A₃₂ = 5 x (-1)³⁺²\(\begin{vmatrix} 2 &5 \\[0.3em] 6 & 4 \\[0.3em] \end{vmatrix}\)

= - 5(8 - 30)

= - 5 x -22 = 110