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平面向量数量积的意义

> 已知△ABC中，角A、B、C的对边分别为 a、 b、 c，AH为BC边上的高，以下结论： ① ② ③ ④ 其中结论正确的个数是（ *** ） A．1 Ｂ．2 Ｃ．3 Ｄ．4

问题：

发布时间：2024-09-11

已知△ABC中，角A、B、C的对边分别为 a、 b、 c，AH为BC边上的高，以下结论： ①                   ②
③         ④
其中结论正确的个数是（ *** ）
A．1      Ｂ．2        Ｃ．3      Ｄ．4

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