If then verify that A^TA = I₂.

6

For the matrices, A and B, verify that (AB)^T = B^TA^T, where

7

If and find A^T – B^T.

9

If verify that A^TA = I₂.

10

If denote the direction cosines of three mutually perpendicular vectors in space, prove that AA^T = I, where