If a is a matrix of order n and the determinant of a is 3, then | 2A inverse-a*|=

If a is a matrix of order n and the determinant of a is 3, then | 2A inverse-a*|=

|2A inverse - A * | = | 2A * / | a | - A * | = | (2e / | a | - E) a * | = | 2E / | a | - e |*|
=|-1/3E||A|^(n-1)=(-1/3)^n*3^(n-1)=(-1)^n/3

A is a square matrix of fourth order, and | a | = 3. Then | 2A | =? A * | =? What is the determinant of the inverse matrix of a?

A is a square matrix of order 4, and | a | = 3. Then | 2A | =? (a *) * = 1 / | a | · a, | a * = | a | ^ (n-1) | Ka |

If M > N, the determinant of AB is proved to be 0
Brothers and sisters, do me a favor! It's exercises on the line

The question should be like this
r(AB)