如图,在四棱锥
中,底面
是边长为2的菱形,
,平面
平面
,点
为棱
的中点.
![](https://img.xkw.com/dksih/QBM/2022/1/6/2888496258179072/2889214410711040/STEM/65f3016d63754590863fcbfc5f8bdf55.png?resizew=118)
(1)求证:
;
(2)若
与平面
所成角为
,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/8469f2a84fbce3195e31ddd413e5f8ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16b77a5c3865855fbb3d24f9522ced8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2022/1/6/2888496258179072/2889214410711040/STEM/65f3016d63754590863fcbfc5f8bdf55.png?resizew=118)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbd7c2767c106faf27d6a97ebc8e739.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d733daf111889f16d5404b731d40fd12.png)
更新时间:2022-01-07 10:24:40
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,四面体
中,已知
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/33c8568a-7f21-4e6a-846f-169e96bb83e6.png?resizew=151)
(1)求证:
;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37569f630a9ca7f70994a9f0f88aaef5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d783fe7f3ce673d5d21281174e7a7968.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/33c8568a-7f21-4e6a-846f-169e96bb83e6.png?resizew=151)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ec2524be492bca0d1566bf848066f10.png)
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【推荐2】如图,已知
是上、下底边长分别为2和6,高为
的等腰梯形,将它沿对称轴
折叠,使二面角
为直二面角.
![](https://img.xkw.com/dksih/QBM/2018/1/18/1863291991629824/1863736903114752/STEM/192b3c32806b417589b891fb31b56eb1.png?resizew=340)
(1)证明:
;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/192f4f9446c954a291f779d963f90257.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd9af670165433e61227ef5d6a73d62.png)
![](https://img.xkw.com/dksih/QBM/2018/1/18/1863291991629824/1863736903114752/STEM/192b3c32806b417589b891fb31b56eb1.png?resizew=340)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/400d97da3779f117510058b0526df75a.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb8faef5f821d00d9c69e65e0988fe1f.png)
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【推荐3】如图,四棱锥
的底面
为筝形,
于
点,
为
的五等分点,
,
,
,且
.
![](https://img.xkw.com/dksih/QBM/2023/7/23/3287019484471296/3287389022994432/STEM/254a252ff1bd47da8f9e952c3705be52.png?resizew=183)
(1)求证:
;
(2)作出平面
与平面
所成二面角
的任意一条棱,并求该二面角
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/5762cefdf4b2edebd125c1e0620734bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd946dad8b716592833a7bc14045a6d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/398fbc0610195cb3793a6520a160c59d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9159748d09dc452605d7bffcec904f8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfaf06273e4ef4aebd47b6aaf24e26aa.png)
![](https://img.xkw.com/dksih/QBM/2023/7/23/3287019484471296/3287389022994432/STEM/254a252ff1bd47da8f9e952c3705be52.png?resizew=183)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbd7c2767c106faf27d6a97ebc8e739.png)
(2)作出平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0cbbcc3d79bf999588882e7b1b4324.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
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解答题-证明题
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适中
(0.65)
解题方法
【推荐1】如图所示,三棱柱
中,
,面
面
,
,
与
相交于
.
(1)求证:
面
;
(2)求三棱锥
的体积;
(3)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90e17995e2f71e297d94ae51c7e5b1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/140088b0cb73812aa9d523c44559298a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/417c6bfed602f1ce7eb594a3570f00fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beb3f621855385d885b7b598dec694b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/861d61d2b7b16e12fd97f870fb3fa522.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/513d1fb90e198a552a61d535187a2fe5.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705248362496/1570705253834752/STEM/583ea6ea-6322-492b-8424-f7968a9910ae.png?resizew=299)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,已知三棱台ABC﹣A1B1C1中,平面BCC1B1⊥平面ABC,△ABC是正三角形,侧面BCC1B1是等腰梯形,AB=2BB1=2B1C1=4,E为AC的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/656188c8-f135-4dad-8454-5ef92818d626.png?resizew=134)
(1)求证:AA1⊥BC;
(2)求直线EB1与平面ABB1A1所成角的正弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/656188c8-f135-4dad-8454-5ef92818d626.png?resizew=134)
(1)求证:AA1⊥BC;
(2)求直线EB1与平面ABB1A1所成角的正弦值.
您最近一年使用:0次
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名校
【推荐1】在多面体
中,四边形
是正方形,
平面
,
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/75ee2df8-5b7f-4bc6-8692-351f3f46103f.png?resizew=147)
(1)求证:
;
(2)求平面
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac0b72906641ed13716cfbce50923282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/868ae15e0ff5af9798d3698910cabf44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8215442c41f8f911e7aec1853cf105ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/75ee2df8-5b7f-4bc6-8692-351f3f46103f.png?resizew=147)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/858bab4f7ca681a83a0f3e95feb740a2.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a09d9d486b7f91ba933210dd013a7f2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
名校
解题方法
【推荐2】如图,
是直角梯形,
,
,
,又
,
.
(1)求证:平面
平面
;
(2)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e61ce105fc9653b120d6901b32780f03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8432a44f6c6b37f4961dc63521fa7f9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b31701eb30785ad7481acc7b377c7625.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c79a65e11d22c1e661d135c39481fbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a1be17e0a3e51cde1f50f384198e71e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bafa8c14100a4f847b41b9148954116c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/3/1cae5cee-df07-4fe2-911b-61ab5326587b.png?resizew=212)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/324a1792318a3528772781fac2b4d2e4.png)
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【推荐1】如图所示,在几何体EFG-DABC中,四边形ABCD,CDGF,ADGE均为正方形,且边长均为1,点M在棱DG上.
![](https://img.xkw.com/dksih/QBM/2022/8/11/3042091438981120/3042451042631680/STEM/fc28f8ecc4a248ed86c2420ec8f7b4d6.png?resizew=183)
(1)求证:BM
EF.
(2)当DM的长为多少时,使得直线MB与平面BEF所成的角为45
?
![](https://img.xkw.com/dksih/QBM/2022/8/11/3042091438981120/3042451042631680/STEM/fc28f8ecc4a248ed86c2420ec8f7b4d6.png?resizew=183)
(1)求证:BM
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
(2)当DM的长为多少时,使得直线MB与平面BEF所成的角为45
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
解题方法
【推荐2】如图,在四棱锥
中,侧面
底面
,底面
是直角梯形,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/a9b6d211-dcd8-47f9-8d1d-ab69996a2a19.png?resizew=265)
(1)证明:平面
平面
;
(2)在线段
上是否存在点M,使得直线
与平面
所成角的正弦值为
?若存在,求出线段
的长度;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3600cc54d6dbbd3b3181e9896035779d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/a9b6d211-dcd8-47f9-8d1d-ab69996a2a19.png?resizew=265)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78a3fd5284e160896f07ce367645fd04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83303d3784492506fc44f2b4d6b07bc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
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