Definite Integral (BIG BOSS)

1. Oct 31, 2004

logicalman

Who can solve or give hint for the following integral?

$$\int_0^4 3x \sqrt{5^2-x^2}dx$$ :tongue:

2. Oct 31, 2004

Hurkyl

Staff Emeritus
Try a technique you learned in class!

3. Oct 31, 2004

mathlete

Try $$u=5^2-x^2$$, which means $$du = -2xdx$$

4. Oct 31, 2004

logicalman

Thanks!

$$u^2=5^2-x^2$$ << This one works better. :tongue: