21. 证明: $\lim\limits_{x\rightarrow 0}x\ln(\sin x)=0$.
Posted by haifeng on 2021-12-28 21:15:15 last update 2021-12-28 21:51:57 | Answers (2) | 收藏
证明:
\[\lim_{x\rightarrow 0}x\ln(\sin x)=0.\]
\[\lim_{x\rightarrow\frac{\pi}{2}}\ln(\cos x)\cdot\ln(\sin x)=0.\]