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在锐角△ABC中,∠BAC=60°,BD、CE为高,F是BC的中点,连接DE、E...
在锐角△ABC中,∠BAC=60°,BD、CE为高,F是BC的中点,连接DE、EF、FD.则以下结论中一定正确的个数有( )
①EF=FD;②AD:AB=AE:AC;③△DEF是等边三角形;
④BE+CD=BC;⑤当∠ABC=45°时,BE=
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DE.
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A.2个
B.3个
C.4个
D.5个
考点分析:
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