Posted by haifeng on 2015-01-08 20:10:26 last update 2015-01-08 20:10:26 | Answers (1) | 收藏
设 $f\in C^1[a,b]$, 且 $f(a)=0$, 证明
\[ \int_a^b f^2(x)dx\leqslant\frac{(b-a)^2}{2}\int_a^b[f'(x)]^2dx. \]
