CIIM 2010 Problem 1

Given two vectors $v = (v_1,\dots,v_n)$ and $w = (w_1\dots,w_n)$ in $\mathbb{R}^n$ , lets define $v*w$ as the matrix in which the element of row $i$ and column $j$ is $v_iw_j$ . Supose that $v$ and $w$ are linearly independent. Find the rank of the matrix $v*w - w*v.$