Answer
$3log_{2}x-log_{2}y$
Work Step by Step
We know that $log_{b}\frac{x}{y}=log_{b}x-log_{b}y$ (where $x$, $y$, and $b$ are positive real numbers and $b\ne1$).
Therefore, $log_{2}\frac{x^{3}}{y}=log_{2}x^{3}-log_{2}y$.
We know that $log_{b}x^{r}=rlog_{b}x$ (where $x$ and $b$ are positive real numbers, $b\ne1$, and $r$ is a real number).
Therefore, $log_{2}x^{3}-log_{2}y=3log_{2}x-log_{2}y$.