Problem:

Correct me if i am wrong, but i think i know that the delta x would be 2/n according to (b-a)/n which would also give 2i/n as our right interval. I would then factor out the 2/n and 2i/n and get 4/n^2. So i would end solving the limit of n -> infinity of

$\displaystyle \frac{4}{n^{2}}\left( \frac{n\left( n+1 \right)}{2} \right)^{2}$

trouble is im not sure how to evaluate this limit because the whole thing wrapped around the exponent is throwing me off.