1. ## Evaluating the integral:

10x(5x^2 - 3)^4 dx

I got it to [10x (5x^2)^5]/5

First off, is this correct? And if so, should it be simplified?

2. Not quite.

$\displaystyle \displaystyle \int 10x(5x^2 - 3)^4 \,dx$

\displaystyle \begin{aligned} u &= 5x^2 - 3 \\ du &= 10x \,dx \end{aligned}

\displaystyle \begin{aligned} \displaystyle \int u^4 \,du &= \dfrac{u^5}{5} + C \\ &= \dfrac{1}{5}(5x^2 - 3)^5 + C \end{aligned}

3. Okay, so if the 10x is already there you don't have to put it back in the problem?

4. That's right, you don't.

5. Okay, thanks guys. That probably explains some of my other problems. I really appreciate it.