如图所示,在矩形
中,
,
,
为
的中点,沿
将△
翻折,使二面角
为直二面角.
![](https://img.xkw.com/dksih/QBM/2021/12/24/2879458204426240/2880095439290368/STEM/7748ca21-eb0b-481c-a3cb-d5f4de119ac5.png?resizew=431)
(1)求证:
;
(2)求
与平面
所成角的大小;
(3)求二面角
的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cdd9f345915ae742ed3dcd3f9678264.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9f79d7939c88e9702962e5917cad290.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97a9b32570d553161be04d13954e92a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f18a490a22cac27417ddc794f00a1941.png)
![](https://img.xkw.com/dksih/QBM/2021/12/24/2879458204426240/2880095439290368/STEM/7748ca21-eb0b-481c-a3cb-d5f4de119ac5.png?resizew=431)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4151e948feebdf7b91fbe739feafa9bc.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a6c6e7c025362c46a64a8956761f08e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/164e1cc74e41a2a55d3767c006392bfd.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3db1d8f228c87b65a3609f825fc441d5.png)
更新时间:2021-12-25 13:12:04
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】四棱台被过点
的平面截去一部分后得到如图所示的几何体,其下底面四边形
是边长为2的菱形,
,
平面
,
.
(Ⅰ)求证:
;
(Ⅱ)求点
到平面
的距离..
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08e1120f005fb701c407fbfd9c1b1302.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f945a69cf7e8213e50622125cde652f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d25e8fc3dda4f8b45491514b6e22a962.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5791c12595e208264669378dd499de56.png)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b8bd2dad6de37bd03e085bcd1976556.png)
(Ⅱ)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14b8f65872fbe939603c6e2acee74baa.png)
![](https://img.xkw.com/dksih/QBM/2018/3/18/1904933540167680/1905563173707776/STEM/9198d5209a3749459a96ab750ed1e678.png?resizew=134)
您最近一年使用:0次
解答题-证明题
|
适中
(0.64)
【推荐2】如图,在正方体
的棱长为
,
为棱
上的一动点.
![](https://img.xkw.com/dksih/QBM/2016/1/8/1572426203447296/1572426209640448/STEM/907791da61de4c1abf4828d583b0b46f.png)
(1)若
为棱
的中点,
①求四棱锥
的体积
②求证:面
面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
(2)若
面
,求证:
为棱
的中点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8456cee87c4e22351affc28f3a73a0f2.png)
![](https://img.xkw.com/dksih/QBM/2016/1/8/1572426203447296/1572426209640448/STEM/6afb1a5d485e4cc1989907df20d5a419.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2016/1/8/1572426203447296/1572426209640448/STEM/907791da61de4c1abf4828d583b0b46f.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
①求四棱锥
![](https://img.xkw.com/dksih/QBM/2016/1/8/1572426203447296/1572426209640448/STEM/45f810e02fae4f7481f953862e7fe31d.png)
②求证:面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a1417fb5959d95e3b23831ff7c3c2dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f5830646a912c3a916beac4f88c116b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】在正四棱锥
中,若异面直线
与
所成角的正切值为2,底面边长
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/0ecaf1fe-0cf6-44b0-bd02-c532521c5d50.png?resizew=162)
(1)求侧棱与底面
所成角的大小;
(2)求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/0ecaf1fe-0cf6-44b0-bd02-c532521c5d50.png?resizew=162)
(1)求侧棱与底面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
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解答题-问答题
|
适中
(0.65)
【推荐2】如图,有一个圆锥形花篮,母线长为20cm,在花篮口的点P处用一根绳子将花篮挂在墙面上,当绳子的长度最短时,可以紧紧箍住花篮,不会上下滑动,已知绳子的长度是20cm.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/11/6f38cc38-b8e5-4ffe-bcfe-37d7919ce014.png?resizew=77)
(1)求花篮的底面半径;
(2)求母线OQ与水平地面所成角的大小.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/11/6f38cc38-b8e5-4ffe-bcfe-37d7919ce014.png?resizew=77)
(1)求花篮的底面半径;
(2)求母线OQ与水平地面所成角的大小.
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图所示,在四棱锥P-ABCD中,底面ABCD是矩形,PD=DC=2BC=2,PD⊥平面ABCD,E是PC的中点,过E作EF⊥PB交PB于F.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/31/20513056-7adc-407e-b129-e2f31a94ad4a.png?resizew=185)
(1)求证:平面PBD⊥平面DEF;
(2)求二面角C-PB-D的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/31/20513056-7adc-407e-b129-e2f31a94ad4a.png?resizew=185)
(1)求证:平面PBD⊥平面DEF;
(2)求二面角C-PB-D的余弦值.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,在四棱锥
中,底面
为矩形,平面
底面
,
为正三角形,E是AB的中点,
.
的距离.
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3830259f36d7a7017c1a488847b1f517.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b37793a3a810e823e10c340986f55ddd.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c9370f39106158d21c44ba4dde6f76.png)
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解答题-问答题
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适中
(0.65)
名校
【推荐3】如图,在五面体
中,
,
平面
,
.已知
,
,
,且
.
平面
;
(2)求平面
与平面
的夹角的余弦值的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62ab061ed9ec918926f1defceb85924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c3e9ef3e849788645552cfb0735d987.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d927585a17c2e98ef7d5a9589a26ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f9b0421e0b4d74b22df706578b74a58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/563f3214a5f5ce732a91be9038ee0468.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15e58659e6ee4d93650e2edb6d6f7ff.png)
您最近一年使用:0次