# Integration / substitution

## Homework Statement

http://img20.imageshack.us/img20/112/41590752.jpg [Broken]

## The Attempt at a Solution

I have no idea how to convert the left equation into the right one.

Could someone show me how to do that?

I don't understand why the right equation should be multiplied by 1/2

It is really giving me a headache.

Last edited by a moderator:

substitute $$u=1 + \mu^2$$ therefore $$du=2 \mu d \mu$$ the half comes in becuase you have to solve for $$\mu d \mu$$ which is in the numerator, it becomes $$\frac{1}{2}du= \mu dx$$