问题
选择题
已知直线l的一个方向向量
|
答案
因为
•a
=（-2，3，1）•（4，0，8）=-2×4+3×0+1×8=0，所以n
⋅a
=0，即n
⊥a
．n
所以
∥α，所以直线l∥平面α或l⊂平面α．a
故选B．
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已知直线l的一个方向向量
|
因为
•a
=（-2，3，1）•（4，0，8）=-2×4+3×0+1×8=0，所以n
⋅a
=0，即n
⊥a
．n
所以
∥α，所以直线l∥平面α或l⊂平面α．a
故选B．
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