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已知向量a=(1,1),b=(2,x),若a+b与4b-2a平行,则实数x的值是...
已知向量a=(1,1),b=(2,x),若a+b与4b-2a平行,则实数x的值是( )
A.-2
B.0
C.1
D.2
考点分析:
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