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.
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.
找出不属于同类词的一项。 | |||
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