如图,多面体
,四边形
是矩形,梯形
平面
,
为
中点,
.
![](https://img.xkw.com/dksih/QBM/2024/1/15/3411850336886784/3412267611127808/STEM/170c424651404fa3865b5c884abf2ab2.png?resizew=166)
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
平面
;
(2)求平面
和平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a685fd7539b94dcede33055ef3b0e340.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1953be42cd629684fea9a22a423ecb2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e50b2e53c74dba074cc314b6e6b7890b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4079b8e3e53b0de4fe767379147028bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b0c05e82af84e3d87046555342208fd.png)
![](https://img.xkw.com/dksih/QBM/2024/1/15/3411850336886784/3412267611127808/STEM/170c424651404fa3865b5c884abf2ab2.png?resizew=166)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df21b7b7a47318ef2bb069450c39f1cd.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/588690c4a218025937357ffab8d63c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82cb18c10820d927ecd53326f58aaf8f.png)
更新时间:2024-01-30 22:09:11
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,四棱锥
在底面是矩形,
平面
,
、
分别是
、
的中点,
,
.
![](https://img.xkw.com/dksih/QBM/2021/11/19/2854656446234624/2857312600834048/STEM/b836c123-082b-4d52-a78d-8c811f583aaa.png?resizew=261)
(1)求证:
平面
;
(2)若直线
与平面
所成的角为
,求直线
与平面
所成的角的大小.
![](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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc11331a7b2d2619b40ee6d34c3bd620.png)
![](https://img.xkw.com/dksih/QBM/2021/11/19/2854656446234624/2857312600834048/STEM/b836c123-082b-4d52-a78d-8c811f583aaa.png?resizew=261)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e5fa72f2878b476bc57f0df12d6555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
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名校
【推荐2】如图,在多面体ABCDEF中,梯形ADEF与平行四边形ABCD所在平面互相垂直,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/11/3436b78d-4c44-4e6a-a1ca-af5490d17e0e.png?resizew=166)
(1)求证:BF∥平面CDE;
(2)求二面角
的余弦值;
(3)判断线段BE上是否存在点Q,使得平面CDQ⊥平面BEF?若存在,求出
的值,若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82438cf7dddee8f62aaa928ce402f96e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/11/3436b78d-4c44-4e6a-a1ca-af5490d17e0e.png?resizew=166)
(1)求证:BF∥平面CDE;
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19fa7ff056747ebdc342dc2ddf1b4b16.png)
(3)判断线段BE上是否存在点Q,使得平面CDQ⊥平面BEF?若存在,求出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72fa6b0921ac2aabed4c310cbb377a2f.png)
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解答题-问答题
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适中
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名校
【推荐1】如图所示的几何体为一个正四棱柱被两个平面AEH与CFG所截后剩余部分,且满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
平面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/11/25b9af69-c06a-439f-921f-385628bdebc2.png?resizew=193)
(1)当BF多长时,
,证明你的结论:
(2)当
时,求平面
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72406478fda1c6e3b8052467385a3bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79de6eb78cbadaf41909c3d50c4c6344.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d37cb657446616b7d679dfd9d2bbef5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1186958b8b5f741230ee3f66f774453c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/11/25b9af69-c06a-439f-921f-385628bdebc2.png?resizew=193)
(1)当BF多长时,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e79216c6a32bb699aeb36144da020490.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e79216c6a32bb699aeb36144da020490.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72406478fda1c6e3b8052467385a3bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09219dbd440c70d66bf2bf8b4c2bfe2f.png)
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解答题-问答题
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【推荐2】已知四棱锥
的底面
是梯形,
,
,
,
,
在棱
上且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/f2155f89-54a1-44bc-a5c1-e164783f9a55.png?resizew=174)
(1)证明:
平面
;
(2)若
平面
,异面直线
与
所成角的余弦值为
,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/68d31600cba2d5256c7e78b6122d6755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce0d7095ddd69d6ceaf1065b1bc2c79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27db558e8db4c957654c8e5cecd2d2dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40560ea08d6cd8c1d4d9661ee6faaa3b.png)
![](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/1b384315ba84cafb978ef3619c8162b5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/f2155f89-54a1-44bc-a5c1-e164783f9a55.png?resizew=174)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c372d059202ec388960b125d4a87dc84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d682fd0344452998187cb6d48de3dd1.png)
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