Find an expression in terms of n for summation

[elitewarr]

Homework Statement

By first expressing the general term in partial fractions, find an expression in terms of n for
summation of r=2 to n ( 1 / (r^2 - 1) ). Hence show that summation of r=1 to n ( 1 / r^2) i less than 7/4 for all values of n

Homework Equations

The Attempt at a Solution

I solved the first part of the question already. However, I'm stuck at the second part. Can anyone give me some clues to showing 1/r^2 sum from r = 1 to n is always less than 7/4?
Thank you.

 

[HallsofIvy]

Well, what did you get for the first part? I suspect that is important to solving the second part!