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如图,在直四棱柱ABCD-A
1B
1C
1D
1中,底面ABCD为平行四边形,且AD=2,AB=AA
1=3,∠BAD=60°,E为AB的中点.
(Ⅰ)证明:AC
1∥平面EB
1C;
(Ⅱ)求直线ED
1与平面EB
1C所成角的正弦值.
考点分析:
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