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如图,已知正方形ABCD和矩形ACEF所在的平面互相垂直,AB=
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,AF=1,M是线段EF的中点.
(1)求证AM∥平面BDE;
(2)求二面角A-DF-B的大小;
(3)试在线段AC上一点P,使得PF与CD所成的角是60°.
考点分析:
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