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设l、m是两条不同的直线,α、β是两个不同的平面,给出下列5个命题: ①若m⊥α...
设l、m是两条不同的直线,α、β是两个不同的平面,给出下列5个命题:
①若m⊥α,l⊥β,则l∥α;
②若m⊥α,l⊂β,l∥m,则α⊥β;
③若α∥β,l⊥α,m∥β,则l⊥m;
④若α∥β,l∥α,m⊂β,则l∥m;
⑤若α⊥β,α∩β=l,m⊥l,则m⊥β.
其中正确命题的个数是( )
A.1
B.2
C.3
D.4
考点分析:
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