- #1

nicknaq

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## Homework Statement

Let A be a 3x3 matrix with determinant 5. Then det(adj(A^T))=____, det(adj(A^−1))=____ and det(adj(7A))=____.

## Homework Equations

Well, I know that the the adjoint is the transpose of the matrix of cofactors.

Also, these may be useful:

A^-1=adj(A)/det(A)

Aadj(A)=det(A)I

adj(A^T)=(adj(A))^T

A*adj(A)=det(A)*I

## The Attempt at a Solution

There's not much process involved in the questions, so I haven't really had an attempt. Thanks for the help.