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[几何] 求$\triangle APB$面积与$\triangle APC$的面积比的最大值

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isee posted 2017-9-6 15:30 |Read mode
题目:设等边三角形$ABC$的内切圆$I$半径为$2$,点$P$满足$PI$=1,求$\triangle APB$面积与$\triangle APC$的面积比的最大值。

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游客 posted 2017-9-7 09:32
sin∠IAP=PI/IA=1/4

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original poster isee posted 2017-9-7 15:37
回复 2# 游客


    有点问题,当$P,I,A$三点共线时,比值为$1>1/4$.

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游客 posted 2017-9-8 08:04
Last edited by 游客 2017-9-8 08:14回复 3# isee


    1/4不是最值,是最值的条件。
未命名.PNG

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original poster isee posted 2017-9-8 09:39
回复 4# 游客


    哈哈,原来是这个意思

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其妙 posted 2017-9-18 00:06
分数的等比定理,解法就来了,游客

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