Let $B$ = {$\vec v_1,\ldots,\vec v_n$} be an orthonormal basis for $R^n$ and let $P$ = [$\vec v_1 \dots \vec v_n$]. Show that for any $\vec x \in \mathbb R^n$ we have $[\vec x]_B = P^T \vec x$
Should I begin by rewriting the right hand side as a inner product?