如图,△ABC中,CD、BE分别是高,M、N分别是线段BC、DE的中点.
(1)求证:MN⊥DE;
(2)若∠A=α,求∠DME的度数(用含α的式子表示).
(3)若将锐角△ABC变为钝角△ABC,直接写出∠DME与∠BAC的数量关系.
(1)求证:MN⊥DE;
(2)若∠A=α,求∠DME的度数(用含α的式子表示).
(3)若将锐角△ABC变为钝角△ABC,直接写出∠DME与∠BAC的数量关系.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/26/19fa5b97-404f-43a5-b191-e26853d5c194.png?resizew=390)
更新时间:2021-01-08 11:48:44
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【推荐1】如图,已知BE是△ABC的角平分线,CP是△ABC的外角∠ACD的平分线.延长BE,BA分别交CP于点F,P.
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