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平面向量数量积的意义

> 下列命题中正确的是（） A．若a×b＝0，则a＝0或b＝0 B．若a×b＝0，则a∥b C．若a∥b，则a在b上的投影为|a| D．若a⊥b，则a×b＝(a×b)2

问题：

发布时间：2024-09-09

下列命题中正确的是（）

A．若a×b＝0，则a＝0或b＝0 B．若a×b＝0，则a∥b

C．若a∥b，则a在b上的投影为|a| D．若a⊥b，则a×b＝(a×b)²

参考答案：

提问用户：Pr***qyg

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下列命题中正确的是（ ） A．若a×b＝0，则a＝0或b＝0 B．若a×b＝0，则a∥b C．若a∥b，则a在b上的投影为|a| D．若a⊥b，则a×b＝(a×b)2

可能感兴趣的题目：

下列命题中正确的是（）

A．若a×b＝0，则a＝0或b＝0 B．若a×b＝0，则a∥b

C．若a∥b，则a在b上的投影为|a| D．若a⊥b，则a×b＝(a×b)²