如图,正四棱锥
的底面边长为2,侧棱长是
,点
为侧棱
上的点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/4/e99fb323-5de7-42dc-9790-5e51e6c4b148.png?resizew=147)
(1)求正四棱锥
的体积;
(2)若
平面
,求二面角
的大小;
(3)在(2)的条件下,侧棱
上是否存在一点
,使得
平面
.若存在,求
的值;若不存在,试说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/defa5b53043ae802bb1af7d14374406d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/4/e99fb323-5de7-42dc-9790-5e51e6c4b148.png?resizew=147)
(1)求正四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fb2e071d4e01107dcf7d95cbb86b415.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc9f1e2b86f4eca37c72011d3dffb0c9.png)
(3)在(2)的条件下,侧棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c372d059202ec388960b125d4a87dc84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9013fec36586592a57b9abfb6ce4ffa.png)
更新时间:2023-02-03 20:41:41
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,
是
的直径,
垂直于
所在的平面,
是圆周上不同于
的任意一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/bab3f338-f9cd-4f9e-9ca0-5869bbd7561f.png?resizew=181)
(1)求证:直线
平面
;
(2)若
,求棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/bab3f338-f9cd-4f9e-9ca0-5869bbd7561f.png?resizew=181)
(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9082547ec262e00ece8072817097d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
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(0.65)
【推荐2】如图,在四棱锥
中,已知
,
,
,
,
,平面
平面
,
.
![](https://img.xkw.com/dksih/QBM/2017/12/16/1839507261874176/1840300957433856/STEM/60d4469c17464a7d924d16eb21c118e1.png?resizew=210)
(1)求证:
平面
;
(2)已知
点在棱
上,且
平面
,若
,求三棱锥
的体积
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e673ef2d48215ca84a48377f17d6df00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b37591109b0a0ec5ffe2133f83310eca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd6a2b112facda441f4e34bf5c145fa.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/4cbb05b8b630052ff544249ebd72d95d.png)
![](https://img.xkw.com/dksih/QBM/2017/12/16/1839507261874176/1840300957433856/STEM/60d4469c17464a7d924d16eb21c118e1.png?resizew=210)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffc3380658a60e5c139bc30572e0e98c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6439082496df7567acd5a31a3448db71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3015db5ca1f49bb7bad43657e06863ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8db4c05c07b57c15dc512ec3320bb17c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49df4e85c1c560f3c635ce3cea7a104b.png)
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解答题-证明题
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名校
解题方法
【推荐1】如图,在直角梯形
中,
.直角梯形
通过直角梯形
以直线
为轴旋转得到,且使得平面
平面
.M为线段
的中点,P为线段
上的动点.
![](https://img.xkw.com/dksih/QBM/2022/1/21/2899465969164288/2917464006377472/STEM/a15dd2f8-8d19-489a-bc32-357585124aa1.png?resizew=199)
(1)求证:
;
(2)当点P满足
时,求证:直线
平面
;
(3)是否存在点P,使直线
与平面
所成角的正弦值为
?若存在,试确定P点的位置;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a611224a391b18f5b90b52eef74e0f9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0671b4776e142e17a79af5b3f0378ef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://img.xkw.com/dksih/QBM/2022/1/21/2899465969164288/2917464006377472/STEM/a15dd2f8-8d19-489a-bc32-357585124aa1.png?resizew=199)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3a5c773af90119232d95de70286a5d2.png)
(2)当点P满足
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/739d47c1e1293a33c333c7e917d5adcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07391ef575d28f09bc5cda0ff8130a54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faa23fa14f624ad8212bda55d321362f.png)
(3)是否存在点P,使直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/438f34bc8b04e8c494b91306ac6fe352.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4e7552a39c412d882766dbcd7eeb69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08d2d3a6c8ede51780d483f6432f7057.png)
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名校
解题方法
【推荐2】如图,四边形
是正方形,
平面
,
,
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/89640fb5-9f19-4de7-b260-fcb0134cc6cc.png?resizew=158)
(1)求证:
;
(2)求二面角
的大小.
(3)在棱
上是否存在点
,使得直线
与平面
所成角的正弦值为
?若存在,求
的长;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f42933ad0b53d1d3eeb494bd591cf2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82465b63174087aeba7788ed984583d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07dd741bc3f02d8552afbcf63fba4fb6.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/editorImg/2023/2/2/89640fb5-9f19-4de7-b260-fcb0134cc6cc.png?resizew=158)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f392902d611863c6908a48e696e7bd8f.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/729a3ac9d8a312996c1aa9eb2e1959fa.png)
(3)在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a424b50eaeafa6f302ffd95476cb86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9068f29d671d76d1e95ba3a4eaff5b96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ec42ae1010746324df9d5d883413526.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在四棱锥
中,
底面
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/12/64ab5b2c-b889-4b16-8efe-3bc9e7478b89.png?resizew=122)
(1)求异面直线
与
所成角的余弦值;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662698361c6b3ddaf0c28a3c87be53e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a755edadca4e4fc27fd49559b8d691ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89f146050a153946cf24ff437fe2a17c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/12/64ab5b2c-b889-4b16-8efe-3bc9e7478b89.png?resizew=122)
(1)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10fc7991ea17d54ff5f4445ac5699463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
您最近一年使用:0次
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适中
(0.65)
名校
【推荐2】如图,在四棱锥
中,底面
为直角梯形,且
,
,侧面
底面
.若
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/27/41e791be-4ac4-42b7-8073-cd9fd486d81f.png?resizew=187)
(1)求证:
平面
;
(2)求平面
和平面
夹角的余弦值;
(3)点
是侧棱
上一点,且直线
和平面
所成角的大小为30°,求
的值.
![](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/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8efa6508d6820f972de28c360aea7504.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/460516ee9c61f1bdd231759be0033e80.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/27/41e791be-4ac4-42b7-8073-cd9fd486d81f.png?resizew=187)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f30533da2e1d2a958dc906c37eba9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(3)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e776b444dff5d435428e6b48740b8b6.png)
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【推荐3】如图,在三棱柱
中,
,顶点
在底面
上的射影恰为点
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/11/5e0f8981-bd0e-481a-aa78-7e2d6358f3cb.png?resizew=177)
(1)证明:
平面
;
(2)
是线段
中点,求平面
和平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d76cef03e6b2d02024495a840ab451.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/11/5e0f8981-bd0e-481a-aa78-7e2d6358f3cb.png?resizew=177)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1c401f9dd333b36433b56d7aef1ffc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e367b683581c7cbe018078168f69efc5.png)
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解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐1】如图,
是边长为6的正三角形,点E,F,N分别在边AB,AC,BC上,且
,
为BC边的中点,AM交EF于点
,沿EF将三角形AEF折到DEF的位置,使
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/ea75ac9a-4ddc-4769-969b-f60f922960d5.png?resizew=254)
(1)证明:平面
平面
;
(2)试探究在线段DM上是否存在点
,使二面角
的大小为
?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b7350dcad9d8d77a32534c90afb7703.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e4a41ee9baa390f2756fc897a5126b8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/ea75ac9a-4ddc-4769-969b-f60f922960d5.png?resizew=254)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f6dd051db98c531f9ef18cdfd793f4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a6480f384476190883f06c0289c7519.png)
(2)试探究在线段DM上是否存在点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e85ca2c9526561962c82c2163c7b7f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ef7c794afde1e5be1fd5c06fe40f75f.png)
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,正方形
与等腰直角三角形
所在平面互相垂直,
,E,F分别是
的中点,G是
上的点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/4e5e5578-966f-4296-9601-68a3d2482d95.png?resizew=142)
(1)试确定点G的位置;
(2)求
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9cf468f5132e14ee1d8cc766808b11af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/374fe9986ebbc986fc422e514ab93a51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb47c199e760eb50b846f2bab89ab9b8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/4e5e5578-966f-4296-9601-68a3d2482d95.png?resizew=142)
(1)试确定点G的位置;
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16b6c178f909ee8ee16fdb58fd2c5fd1.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐3】如图,在梯形
中,
,
,
分别是
的中点,且
交
于点O,现将梯形
沿对角线AC翻折成直二面角
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/8d4fe70a-2405-4c64-b091-85edc1d6126b.png?resizew=438)
(1)证明:
平面
;
(2)证明:
;
(3)若
,试问在线段
上是否存在点
,使得三棱锥
的体积为
?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68d31600cba2d5256c7e78b6122d6755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/848140f6adbe106733afd83009057df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d93949d8a15aca4e79cedb978590571.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ec5639622c38c31424b131cf7c2e797.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/8d4fe70a-2405-4c64-b091-85edc1d6126b.png?resizew=438)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4145f6d9dd03cd2317f9d999991e8c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de1013ac75d1d867331a5851fea34f56.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edbd130a020f4931196a92ea8dc8f828.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a58a622e2b1a239f2f96aa1501e9799.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24006d28116bc097933cc90bcc0ea69f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf5a48d187f8798f5b10c6be04c497b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d599cb4a589f90b0205f24c2e1fa021e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9200f328e82158d59ec5df31a928795.png)
您最近一年使用:0次