如图,四棱锥
中,
平面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2021/5/6/2715425589313536/2716908155797504/STEM/722a3bd5-5ec0-4146-9671-5f879fa2faf7.png?resizew=325)
(1)求证:
平面
;
(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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef699f5dc072b853cfe700c6f1abbbae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f63332d4e33f1a89044a09501b9e0849.png)
![](https://img.xkw.com/dksih/QBM/2021/5/6/2715425589313536/2716908155797504/STEM/722a3bd5-5ec0-4146-9671-5f879fa2faf7.png?resizew=325)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1636b4530c0b42d0e0b649e90e3b9e85.png)
更新时间:2021-05-08 23:46:42
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,在三棱锥D-ABC中,
,
,M,N分别是线段AD,BD的中点,
,
,
,二面角
的大小为60°.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/91788f67-dbce-49bb-ac2f-4ae9d11bee0e.png?resizew=155)
(1)证明:△ABC为直角三角形;
(2)求直线BM和平面MNC所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8915e8e775538d41debf1933102c6b86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd6a2b112facda441f4e34bf5c145fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b810bf15975ccb16c38034b41bb46b0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1719410d21e3de1242366ce2965e838c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/107b87854ea594f77a40b25becd36020.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/91788f67-dbce-49bb-ac2f-4ae9d11bee0e.png?resizew=155)
(1)证明:△ABC为直角三角形;
(2)求直线BM和平面MNC所成角的正弦值.
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,四边形
是一个半圆柱的轴截面,E,F分别是弧
,
上的一点,
,点H为线段
的中点,且
,
,点G为线段
上一动点.
![](https://img.xkw.com/dksih/QBM/2022/4/9/2954584608210944/2955649044578304/STEM/03ac218cc0d148afa5ee26f4c36925d4.png?resizew=151)
(1)试确定点G的位置,使![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
平面
,并给予证明;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd6020b78ff385667b30088ecadeadd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5441d73845911db1993bf903c4d8700f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee3b11d0be9f927c242e19991c8ac6c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://img.xkw.com/dksih/QBM/2022/4/9/2954584608210944/2955649044578304/STEM/03ac218cc0d148afa5ee26f4c36925d4.png?resizew=151)
(1)试确定点G的位置,使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630a21ba7a8e1b8bca73c1634cc6f74d.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a36611b597dc88c4f81fb341bbaf27f.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图,在四棱锥
中,底面ABCD是正方形,侧棱
底面ABCD,
,E是PC的中点.
![](https://img.xkw.com/dksih/QBM/2021/11/17/2853138512404480/2858054318891008/STEM/c8253f54-180f-4671-8d69-572eb963ac5d.png?resizew=286)
(1)求证:
平面PBD;
(2)求PB与平面BDE所成角的正弦值;
(3)求点A到平面BDE的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43d4c42112e0a22f240ce2ae432e5b4d.png)
![](https://img.xkw.com/dksih/QBM/2021/11/17/2853138512404480/2858054318891008/STEM/c8253f54-180f-4671-8d69-572eb963ac5d.png?resizew=286)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56fdf217165748fafe938b64fa08179.png)
(2)求PB与平面BDE所成角的正弦值;
(3)求点A到平面BDE的距离.
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,四棱锥
中,
平面
,
,
,点
在棱
上,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/13/f0991ddc-c407-4399-94d8-a3ef177f7c7f.png?resizew=329)
(1)求证:
平面
;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.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/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5acb763021bf166ca719d07223591d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45ab1959f7fa560977ffb9fb0e11bb2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e7b6d04f024ca05cdfacc8ce9137c15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d5a2cd05e4476fc72271e8fdb59a9a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/13/f0991ddc-c407-4399-94d8-a3ef177f7c7f.png?resizew=329)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44b190c8d3d7d7d0e6e959e8a52eae90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db04e82f03e6216886d416b35abe85a3.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
【推荐2】如图①在直角梯形ABCP中,
,
,
,
,E,F,G分别是线段PC,PD,BC的中点,现将
折起,使平面
平面ABCD如图②.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/3ad1ce45-ab3a-4f78-a677-3f4653651302.png?resizew=316)
(1)求证:
平面EFG;
(2)求二面角G—EF—D的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ace3f86d71ba55a0bd713a047e5b33c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0910601e7d760188d10beee6a48f2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fb46c641aa0616b3b09d596dda500ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36aae82d53f2a35d2f95f467bd5b76cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ad6a0124359e8b9f7649cf0bff51ab.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/3ad1ce45-ab3a-4f78-a677-3f4653651302.png?resizew=316)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d8677ae5ca7acf874d93789425d172.png)
(2)求二面角G—EF—D的大小.
您最近一年使用:0次