Walkthrough of these two integral questions?

[annoying]

So, I have the answer but I don't know how the question got from the start to end.

I've tried different ways but get stuck. I don't know how to rearrange the function to make an easy u substitution.

http://img713.imageshack.us/img713/7367/screenshot20111028at200.png

 

[HallsofIvy]

For (1), let u= ln(t). What is du?

For (2), let $u= tan^{-1}(x)= arctan(x)$. What is du?