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[几何] 2011年全国高中数学联赛B卷第7题.有纯几何解法吗?

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aishuxue Posted at 2014-2-15 22:52:06 |Read mode
在$\trangleABC$中,$E,F$分别是$AC,AB$的中点,$AB=\dfrac{2}{3}AC$.若$\dfrac{BE}{CF}<t$恒成立,则$t$的最小值为_____.

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 Author| aishuxue Posted at 2014-2-15 22:55:22
除了中线长公式,或直接使用余弦定理,有更为简单的几何方法吗?

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goft Posted at 2014-2-15 23:11:46
特殊值法,依照提议,t肯定娶不到,那就是说不是三角形的时候,后略

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2025-4-21 23:53 GMT+8

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