Solution
= Solution
Transpose both inverse identities, using reversal of multiplication under <matrix transposition>:
$$
(A^{-1})^TA^T=(AA^{-1})^T=I,\qquad A^T(A^{-1})^T=(A^{-1}A)^T=I.
$$
Thus \b[$(A^T)^{-1}=(A^{-1})^T$], by uniqueness of the <matrix inverse>.