# How can I solve this indefinite integral?

Can someone please show me with steps on how to evaluate this indefinite integral?

Let $u = \sin x \implies du = \cos x\,dx$.
$$\int 3(\,\underbrace{\sin(x)}_{u}\,)^3 \,\underbrace{\cos x\,dx}_{du}= \int 3u^3 \,du$$
• Yes, $\frac 34 u^4 + C$. And then back substitute: that gives us $\frac 34 \sin^4 x + C$ – Namaste Mar 1 '14 at 0:35