向量a、b满足|a|=1,|b|=,(a+b)⊥(2a-b),则向量a与b的夹角为A.45° �

向量a、b满足|a|=1,|b|=,(a+b)⊥(2a-b),则向量a与b的夹角为

A.45° B.60° C.90° D.120°

答案

C ∵(a+b)⊥(2a-b),∴(a+b)·(2a-b)=2a²-b²+a·b=a·b=0a⊥b.

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向量a、b满足|a|=1,|b|=,(a+b)⊥(2a-b),则向量a与b的夹角为A.45° �

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