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[不等式] 一个与三角形内切圆与外接圆半径相关的不等式

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lemondian Posted at 2024-10-16 14:12:19 |Read mode
Last edited by lemondian at 2024-10-16 15:15:00若$\triangle ABC$的内切圆与外接圆半径分别为$r,R$,记$M=(\cos A+\sin \dfrac{B}{2})(\cos B+\sin \dfrac{C}{2})(\cos C+\sin \dfrac{A}{2})$,试证明或否定:$M\leqslant \dfrac{r}{R}+\dfrac{1}{2}$。

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kuing Posted at 2024-10-16 14:23:11
不是 \ cosA\cos A

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已修  Posted at 2024-10-16 15:16

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 Author| lemondian Posted at 2024-10-17 08:17:12
顶一下

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 Author| lemondian Posted at 2024-10-18 08:59:56

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难道估计很大,没必要顶得这么频  Posted at 2024-10-18 09:22
难不倒kuing的😊  Posted at 2024-10-18 11:34

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 Author| lemondian Posted at 2024-10-22 15:25:27
沉了,再顶一下

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 Author| lemondian Posted at 2024-10-25 19:47:40
看来还是难度不小,快十天了,还没有解答

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 Author| lemondian Posted at 2024-10-29 21:17:15
别人发给我的,也不知是否正确,但相当暴力,完全看不懂!
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相当暴力😵‍💫  Posted at 2024-11-9 19:43

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 Author| lemondian Posted at 2024-11-6 11:42:55
然后再顶一个这帖

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 Author| lemondian Posted at 2024-11-9 19:39:40
kuing:这个有证法么?听说是安老师出的

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 Author| lemondian Posted at 2024-11-16 11:43:31
再顶顶……
希望,希望……

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 Author| lemondian Posted at 2024-11-29 09:34:37
再顶一个这帖

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