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平面向量与的夹角为60°,=(2,0),||=1,则|+2|=( ) A. B....
平面向量
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与
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的夹角为60°,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673822083/SYS201310241834246738220003_ST/2.png)
=(2,0),|
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|=1,则|
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+2
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|=( )
A.
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B.
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C.4
D.12
考点分析:
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