如图,正方体ABCD-A1B1C1D1中,M、N、E、F分别是棱A1B1、A1D1、B1C1、C1D1的中点.
![](https://img.xkw.com/dksih/QBM/2018/12/10/2093695220662272/2095097345335296/STEM/a640d4344e4b45bb823a7af4cfeac0d3.png?resizew=109)
(1)求MN与AC所成角,并说明理由.
(2)求证:平面AMN∥平面EFDB.
![](https://img.xkw.com/dksih/QBM/2018/12/10/2093695220662272/2095097345335296/STEM/a640d4344e4b45bb823a7af4cfeac0d3.png?resizew=109)
(1)求MN与AC所成角,并说明理由.
(2)求证:平面AMN∥平面EFDB.
更新时间:2018-12-12 11:09:22
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解答题-证明题
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解题方法
【推荐1】在四棱锥
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(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
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【推荐2】如图:三棱锥
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解答题-证明题
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解题方法
【推荐1】如图,已知
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