$\displaystyle a_{n} = \frac{1}{n+1} + \frac{1}{n+2} + ... \frac{1}{2n} $
what is the limit ?
Im trying to learn the same things so make sure to check my answer with someone else here but what I noticed is that the difference between each term is 1. Doesn´t that imply that this is an aritmetic series?
There is a formula for that and that is $\displaystyle \sum{a_1}+{a_2}....+a_n = \frac{n(a_1+a_n)}{2}$