已知向量a=(1,x2),b=(x,8),若a∥b,则实数x的值为 () A.2 B.-2 C.±2 D.0

已知向量a=(1,x2),b=(x,8),ab,则实数x的值为 (   )

A.2    B.-2    C.±2    D.0

答案

A

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