# How do you find the integral of (sec^2 x)(tan^2 x) dx?

$\frac{{\tan}^{3} x}{3} + C$
By making a substitution, $\tan x$= $U$, you will get $\mathrm{dU}$ = ${\sec}^{2} x \mathrm{dx}$. Therefore, $\mathrm{dx}$= $\frac{\mathrm{dU}}{\sec} ^ 2 x$. Then the integral will become:
$\int {U}^{2} \mathrm{dU}$. Substitute the value of U and obtain the result.