Posted by haifeng on 2014-11-11 21:26:48 last update 2014-11-11 21:30:13 | Answers (1) | 收藏
证明
\[\int_0^{\frac{\pi}{2}}\frac{\sin x}{1+x^2}dx < \int_0^{\frac{\pi}{2}}\frac{\cos x}{1+x^2}dx.\]