# Some double integration help

1. Oct 23, 2005

### Exulus

Hoping someone can help here. I have to double integrate this:

http://img467.imageshack.us/img467/2171/integrate27rq.jpg

And ive been told that the following expressions are useful:

http://img486.imageshack.us/img486/8706/integrate18yl.jpg

Now..i can integrate once using the second expression, but then i get stuck. Do i either evaluate the first integration and then integrate whats left over or do i integrate again and then evaluate? If i evaluate straight away i seem to get infinity/infinity - infinity/infinity which is 0, and then the whole expression becomes 0. Which seems a bit silly.

I cant see how the first expression helps either.

Hoping someone can give some pointers :(

Last edited by a moderator: Apr 21, 2017