$\"\"$

Consider $\"\"$ and $\"\"$ are inverses of square matrix $\"\"$ .

By definition of inverse matrix, $\"\"$ and $\"\"$ .

Associative property of matrix multiplication : $\"\"$ .

$\"\"$

Therefore, $\"\"$ .

$\"\"$

A square matrix $\"\"$ has inverses $\"\"$ and $\"\"$ then $\"\"$ .