Question

If A and B non-singular matrix then, which of the following is incorrect?

Options

• A² = I implies A^-1 = A

• I^-1 = I

• If AX = B then X = B^-1A

• If A is square matrix of order 3 then |adj A| = |A|²

Answer 1

If AX = B then X = B^-1A