若平面α,β的法向量分別為
=(2,-3,4),=(-3,1,-4),則( �。�
A.α∥β | B.α⊥β |
C.α,β相交但不垂直 | D.以上均不正確 |
假設(shè)存在實數(shù)λ滿足
=λ,則
無解,說明
與
不共線,因此α與β不平行.
又∵
•=2×(-3)-3×1+4×(-4)=-17≠0,
∴平面α,β相交但不垂直.
故選C.
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