Question

Consider this matrix:

Answer 1

let B=adj(A). Find \[b _{31}, b _{32}\]\[b\]

Answer 2

(the entries are in the 3rd row of adjoint of A)

Answer 3

So, do you know how to find the adjugate of a matrix? It's just the transpose of the cofactor matrix. What's the cofactor matrix? It's just where you take matrix A and each number is replaced with the determinant of the 2x2 matrix left when you remove that row and column that the number is in. Then you give each one + or - for every other one. Try it out, and I'll help you.