Use the previous exercise to prove that, if $\alpha$ and $\beta$ belong to $S_{n}$ and $\beta$ is the product of $k$ -cycles of lengths $n_{1}, n_{2}, \ldots, n_{k}$, then $\alpha \beta \alpha^{-1}$ is the product of $k$ -cycles of lengths $n_{1}, n_{2}, \ldots n_{k}$