Let A be a m x n matrix. Prove that A*A is self adjoint
(1) (AB)* = B* A*
(2) X** = X
so
(A* A)* = A* A** = A* A
A*A= (A)2
Comments
(1) (AB)* = B* A*
(2) X** = X
so
(A* A)* = A* A** = A* A
A*A= (A)2