What is a Telescoping Series and How Can It Help Solve This Calculus Problem?

[Frillth]

I got the following problem for my Calculus course:

http://img291.imageshack.us/img291/7449/problemsw3.jpg

I know the answer to this is 2, but I can't seem to make any headway in this problem. Can somebody give me a hint?

 

[StatusX]

Do you know what a telescoping series is? It looks like that series is pretty close to one.