如图,四棱锥
的底面
是边长为2的菱形,
,已知
,E为
的中点.
![](https://img.xkw.com/dksih/QBM/2021/1/5/2629771260780544/2629819574657024/STEM/d4e6896844af4b37b72f40b0b35475f4.png?resizew=206)
(1)求证
;
(2)求直线
与平面
所成角的正弦值.
(3)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/e6906f59d09ce31956d6f5ea2b23fc77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b4c7ccee57161162e10294aecf2b0b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/2021/1/5/2629771260780544/2629819574657024/STEM/d4e6896844af4b37b72f40b0b35475f4.png?resizew=206)
(1)求证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4125524caac016727c80d2722c5ba3.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/914ffeb7d13b8c5801c4dd506344bb83.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db04e82f03e6216886d416b35abe85a3.png)
19-20高一·浙江·期末 查看更多[2]
更新时间:2021-01-05 22:44:31
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】如图,在三棱锥
中,D,E分别为
的中点,且
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/14/1331db55-ac74-4a39-9379-6d871f78791d.png?resizew=170)
(1)证明:
;
(2)若
,求
的周长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c1fa484da37a62e28c5781d7bb4f815.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e16ee7dd17a0f5720b10b6c5d873f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/14/1331db55-ac74-4a39-9379-6d871f78791d.png?resizew=170)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bafa8c14100a4f847b41b9148954116c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60f011304e188e076ca4c78089ca8556.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9524e3810e06dc781285f1289e75d653.png)
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|
适中
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【推荐2】如图1,
,点
为线段
的中点,点
为线段
上靠近
的三等分点.现沿
进行翻折,得到四棱锥
,如图2,且
.在图2中:
![](https://img.xkw.com/dksih/QBM/2020/5/26/2471209337217024/2471687538270208/STEM/9439b224-2678-4d92-84ff-0dbff6155f5f.png?resizew=168)
![](https://img.xkw.com/dksih/QBM/2020/5/26/2471209337217024/2471687538270208/STEM/ca106500-c163-479c-88a0-17166d2aab1d.png?resizew=153)
(1)求证:
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cb2add1954da7c5365e4ef6a9e8bfa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d3071be47c0be1fb8b89afe89fe1816.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f70d6f5baadf8139ee650b84f2fde70.png)
![](https://img.xkw.com/dksih/QBM/2020/5/26/2471209337217024/2471687538270208/STEM/9439b224-2678-4d92-84ff-0dbff6155f5f.png?resizew=168)
![](https://img.xkw.com/dksih/QBM/2020/5/26/2471209337217024/2471687538270208/STEM/ca106500-c163-479c-88a0-17166d2aab1d.png?resizew=153)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d0edb1508fc95765f3bb316bcb5252d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7af6b531f532eb39c26d36e9dd97254d.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59ac7cf883a6e586d06e3f33875bd95b.png)
您最近一年使用:0次
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名校
【推荐1】如图,在四棱锥
中,
,
,底面
是直角梯形,
.
(1)求证:
;
(2)求平面
与平面
的夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7fca40920c70c01c551e83d61e69b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e1b638760d907efe836500581da1596.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86756f44de592bdb3d29b96eb75c31d2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/24/67688748-00c3-4473-83dc-38da262af2e4.png?resizew=151)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4125524caac016727c80d2722c5ba3.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
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解题方法
【推荐2】如图,在四棱锥
中,
是等边三角形,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/faaccb5a-8ef6-4c76-a8bd-802e29995091.png?resizew=279)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89cf8dbc9bc63b426856976d64e83b8.png)
(2)若平面
平面
,
,
求三棱锥
的体积
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6be2b61f4a38e2ee2c1a01e00b3ae6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4020b47658346639e42836fea8e672c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/086b195fa3c01695809ba94ddf0261aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a357959bdb76f0f0eea876857aa8cdb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/faaccb5a-8ef6-4c76-a8bd-802e29995091.png?resizew=279)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89cf8dbc9bc63b426856976d64e83b8.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8acbf7aa8e684b3bb898396d8de8a58e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0051d92c8639713847682826c2bb9783.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/157ddd1b7e7100c31df2fa040e75e908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4875cf47422a791829637e4bd6460844.png)
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【推荐3】如图,在四棱锥
中,底面
为梯形,
,
为等边三角形.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/14/6c68634f-6e84-456c-9599-1beec920c305.png?resizew=156)
(1)证明:
平面
.
(2)若
为等边三角形,求平面
与平面
夹角的余弦值.
![](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/b2201efd8a9dfdcd493019090640c3e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88b6c15b3cffca7663acb8197770091c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/14/6c68634f-6e84-456c-9599-1beec920c305.png?resizew=156)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
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适中
(0.65)
名校
【推荐1】如图,长方体
中,AB=AD=2,A
=4,P为棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/88d83e9e-1b69-4227-aef8-56917085b107.png?resizew=127)
(1)求直线
与平面
所成角的余弦值;
(2)求直线AP被长方体
的外接球截得的线段长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/88d83e9e-1b69-4227-aef8-56917085b107.png?resizew=127)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)求直线AP被长方体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
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【推荐2】如图,三棱柱
中,侧棱
平面ABC,
为等腰直角三角形,
,且
,E,F分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/2020/12/1/2604671249268736/2606821897781248/STEM/d49df3fb65824222893c5f9010dd86b1.png?resizew=161)
(Ⅰ)若D是
的中点,求证:
平面AEF;
(Ⅱ)线段AE(包括端点)上是否存在点M,使直线
与平面AEF所成的角为
?若有,确定点M的位置;若没有,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92105835f8075cb75dff244e908370b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2020/12/1/2604671249268736/2606821897781248/STEM/d49df3fb65824222893c5f9010dd86b1.png?resizew=161)
(Ⅰ)若D是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/debdc6632a4877e5131d3da25cda8b89.png)
(Ⅱ)线段AE(包括端点)上是否存在点M,使直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5e884ca9429486026caa5e2310b0e4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
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【推荐1】如图所示的几何体
中,
平面
,
,
,
,
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/eabcbc25-534b-48b4-b152-a50305ea47b9.png?resizew=203)
(1)求证:
;
(2)若
.
①求直线
与平面
所成角的正弦值;
②二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be89b9d1709d7974a108142c5fa2ccec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7bd02e0adeae92ba9526261b1baf797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48a277db452e76240ec83ec6a2864bdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52bbb16f9380dd62d556480a3944be31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66418ef39d3081d89411a4907d8599f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fdf241efcd0c8026d188fad5a5ba4e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/eabcbc25-534b-48b4-b152-a50305ea47b9.png?resizew=203)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f5ffe436f8eb53a211abf95baed8ca9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66b1a3078dc4803bd5e16833ddd459e0.png)
①求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
②二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7874b5f6364f474023a57e5fe08bc90.png)
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解题方法
【推荐2】已知:如图所示的几何体中,正方形
所在平面垂直于平面
,四边形
为平行四边形,
为
上一点,且
平面
,
.
![](https://img.xkw.com/dksih/QBM/2021/2/2/2649630773452800/2653421974921216/STEM/3bd6dee4d116472288465b34fe15aa68.png?resizew=151)
(1)求证:平面
平面
;
(2)当
时,求平面
与平面
所成二面角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d4ab45e8e8f0084d8d90a4c1233d86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d4ab45e8e8f0084d8d90a4c1233d86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbf65b8884909d735d575efe81a2d2ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://img.xkw.com/dksih/QBM/2021/2/2/2649630773452800/2653421974921216/STEM/3bd6dee4d116472288465b34fe15aa68.png?resizew=151)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63e4d19bf237a6fca67e0d01a9ddb726.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6760f565c694d1cdb6d7068e14526d00.png)
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【推荐3】如图所示,在边长为
的正方形
中,点
在线段
上,且
,
,作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
,分别交
,
于点
,
,作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
,分别交
,
于点
,
,将该正方形沿
,
折叠,使得
与
重合,构成如图所示的三棱柱
.
(1)求证:
平面
;
(2)求四棱锥
的体积;
(3)求平面
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8da45c443af7994a26ffa9d8894e7262.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebb05874eb3353d754af24c9974273e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab609a6574633ebabcff3e73fa862081.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa31b2d885e45b6ad1c0a7cab73111b.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1685f39771b21ab0e9fc5f4abe4aa144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0e81e478fe2b085a15ed001e9b33dae.png)
![](https://img.xkw.com/dksih/QBM/2012/3/6/1570788912168960/1570788917960704/STEM/ca4d0b54-ccd4-4a7e-9670-07a1094b1c14.png?resizew=401)
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