Consider the mapping from $V \otimes V^*$ to $\operatorname{Lin}(V ; V)$ which sends $v \otimes f\left(v\right.$ in $V, f$ in $\left.V^*\right)$ to the linear mapping from $V$ to $V$ which sends $v^{\prime}$ in $V$ to $\left[f\left(v^{\prime}\right)\right] v$. Prove that this is a linear mapping and that it is a monomorphism. Prove that it is an isomorphism if and only if $V$ is finite-dimensional.