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已知平面α、β、γ,直线l,m满足:α⊥γ,γ∩α=m,γ∩β=l,l⊥m.由上...
已知平面α、β、γ,直线l,m满足:α⊥γ,γ∩α=m,γ∩β=l,l⊥m.由上述条件可推出的结论有
①m⊥β ②l⊥α ③β⊥γ ④α⊥β
考点分析:
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