Posted by haifeng on 2014-10-11 19:40:08 last update 2014-10-11 19:40:08 | Answers (1) | 收藏
求极限
\[ \lim_{n\rightarrow\infty}\biggl[\frac{3}{1^2\cdot 2^2}+\frac{5}{2^2\cdot 3^2}+\cdots+\frac{2n+1}{n^2(n+1)^2}\biggr] \]
