Chapter 7.3, Problem 3QCE

Use the indicated substitution to rewrite the integral in terms of u. Do not evaluate the integral.

$\begin{array}{l}\left(\text{a}\right){\displaystyle \int {\sin }^{2}x\cos xdx;u=}\sin x\\ \left(\text{b}\right){\displaystyle \int {\sin }^{3}x{\cos }^{2}xdx;u=}\cos x\\ \left(\text{c}\right){\displaystyle \int {\tan }^{3}x{\sec }^{2}xdx;u=}\tan x\\ \left(\text{d}\right){\displaystyle \int {\tan }^{3}x\sec xdx;u=}\sec x\end{array}$