exercise: evaluate the integral

${\displaystyle \underset{16\text{s}\text{q}\text{u}\text{a}\text{r}\text{e}\text{r}\text{o}\text{o}\text{t}3\text{o}\text{v}\text{e}\text{r}3}{\overset{8\text{s}\text{q}\text{u}\text{a}\text{r}\text{e}\text{r}\text{o}\text{o}\text{t}2}{}}},\frac{\sqrt[\phantom{2}]{x^2-64}}{x}dx$