[求助] 求证三角不等式 已有2人参与

22楼: Originally posted by hylpy at 2016-09-08 09:52:56
@whjwd给出了答案里，有一个小的疑点，如下:
"Because \sin x\leq 1; \sin y\leq 1 and x\neq y, so we obtain
     \left ( x-y \right )^2> \left ( y\sin x-x\sin y \right )^2\geq 2xy\left ( x-y \r ...

2楼: Originally posted by szuwusongbin at 2016-09-04 00:27:12
专家每天放一题啊