1 . 如图所示,在四棱锥
中,四边形
是正方形,点
分别是线段
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/31/684f0061-f471-44fa-b0ef-91fd3df2774a.png?resizew=140)
(1)求证:
;
(2)线段
上是否存在一点
,使得面
面
,若存在,请找出点
并证明;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1e038b4e76b3a368731d3331522b8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1d70676406f26d339465fe3473c0c05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a003de8409231a347edebc8284be186c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85de410d85be189dfa5aabb33410b896.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/31/684f0061-f471-44fa-b0ef-91fd3df2774a.png?resizew=140)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da4cd5cd0de37a81455262f96acaca01.png)
(2)线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f32299ca54d8b38967931d69a218c88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
您最近一年使用:0次
2019-01-26更新
|
2609次组卷
|
19卷引用:【全国百强校】重庆市江津中学、合川中学等七校2018-2019学年高二上学期期末考试数学(理科)试题
【全国百强校】重庆市江津中学、合川中学等七校2018-2019学年高二上学期期末考试数学(理科)试题【校级联考】重庆市江津中学、合川中学等七校2018-2019学年高二上学期期末考试数学(文科)试题安徽省皖北名校2020-2021学年高二上学期第一次联考数学试题安徽省合肥市肥东县第二中学2020-2021学年高二上学期第一次月考数学(理)试题(已下线)2.2.4 平面与平面平行的性质-2020-2021学年高一数学课时同步练(人教A版必修2)福建省厦门一中2020-2021学年高一下学期期中考数学试题湖南省郴州市嘉禾县第一中学2020-2021学年高一下学期第二次月考数学试题湖北省鄂东南三校联考2021-2022学年高一下学期阶段考试(二)数学试题四川省峨眉第二中学校2022-2023学年高二上学期10月月考文科数学试题四川省眉山市2022-2023学年高二上学期期末教学质量检测数学(文)试题四川省眉山市2022-2023学年高二上学期期末教学质量检测理科数学试题安徽省芜湖市华星学校2021-2022学年高一下学期期中数学试题四川省眉山市2022-2023学年高二上学期期末数学(理)试题陕西省西安市鄠邑区2022-2023学年高一下学期期中数学试题陕西省渭南市韩城市新蕾中学2020-2021学年高一上学期第三次月考数学试题云南省红河州开远市第一中学校2022-2023学年高一下学期4月月考数学试题浙江省嘉兴八校联盟2020-2021学年高一下学期期中联考数学试题(已下线)核心考点07空间直线、平面的平行-【满分全攻略】2022-2023学年高一数学下学期核心考点+重难点讲练与测试(人教A版2019必修第二册)江苏省无锡市江阴市三校联考2023-2024学年高一下学期4月期中数学试题
名校
解题方法
2 . 如图,在正四棱锥
中,
是棱
的中点;![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
平面
;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8045011bda83584a9f8d69a8fb2638fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/466fabcaac59132fea648ff35342ec9d.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc9906ec3e92ecdefb55d5b1d99a928e.png)
您最近一年使用:0次
2023-11-10更新
|
604次组卷
|
7卷引用:重庆市长寿中学校2023-2024学年高一下学期学段考试一(4月)试题
重庆市长寿中学校2023-2024学年高一下学期学段考试一(4月)试题重庆市清华中学校2023-2024学年高一下学期4月阶段测试数学试题上海市上海中学2023-2024学年高二上学期期中数学试题(已下线)专题8.10 立体几何初步全章十三大基础题型归纳(基础篇)-举一反三系列(已下线)第十一章:立体几何初步章末重点题型复习(2)-同步精品课堂(人教B版2019必修第四册)(已下线)重难点专题10 轻松解决空间几何体的体积问题-【帮课堂】(苏教版2019必修第二册)青海省西宁市海湖中学2023-2024学年高一下学期第二阶段考试数学试卷
名校
3 . 如图,在直三棱柱
中,
,
为
的中点,点
为
重心.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/861112e7-1c80-4b30-9a82-5115bc0697b4.png?resizew=168)
(1)求证:
面
;
(2)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8e9ec412ea0355e4e5cd06c60e5fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22294aba8268dcd2a1ef3dd3120b1205.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4310db23fc79936c7182361e652bab1a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/861112e7-1c80-4b30-9a82-5115bc0697b4.png?resizew=168)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e60db93cd34a54c98da9ff9782656c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4e7552a39c412d882766dbcd7eeb69.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5e26940501c02cec99f81463710ff51.png)
您最近一年使用:0次
名校
4 . 如图,四边形
是正方形,
平面
,
,
,
,F为
的中点.
![](https://img.xkw.com/dksih/QBM/2022/3/10/2933351405576192/2938037186764800/STEM/ea88ee5151bd4014a6200ea5a6021887.png?resizew=174)
(1)求证:
平面
;
(2)求二面角
的大小.
![](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/85ff59abe5e0a0f35141a78e63da7579.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/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2022/3/10/2933351405576192/2938037186764800/STEM/ea88ee5151bd4014a6200ea5a6021887.png?resizew=174)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f306ff6d237cd9d847aa109acf9333d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bf12905647aeeded72bbca21a63f319.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/729a3ac9d8a312996c1aa9eb2e1959fa.png)
您最近一年使用:0次
2022-03-17更新
|
2684次组卷
|
6卷引用:重庆市名校联盟2022届高三下学期第一次联考数学试题
名校
解题方法
5 . 如图所示,在矩形
中,
,
,点
是线段
的中点,把三角形
沿
折起,设折起后点
的位置为
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/24eb02e2-6f15-4613-b94f-1b2f33386b8a.png?resizew=206)
(1)求证:无论
在什么位置,都有
平面
;
(2)当点
在平面
上的射影落在线段
上时,若三棱锥
的四个顶点都在一个球上,求这个球的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4aca5534bce25acaeb7379deed8f8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.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/97a9b32570d553161be04d13954e92a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.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/2022/11/18/24eb02e2-6f15-4613-b94f-1b2f33386b8a.png?resizew=206)
(1)求证:无论
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dcafa398cc6b6079883e7ad153eb62d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bf12905647aeeded72bbca21a63f319.png)
(2)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f11bfca0b64b54b4b804e460162dc81.png)
您最近一年使用:0次
名校
6 . 如图1,在边长为
等边
中,点D、E分别为边
、
上的中点.将
沿
翻折到
的位置并使得平面
平面
,连接
,
得到图2,点N为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/24/c03d25b0-e600-4419-82bb-135c4be8189e.png?resizew=326)
(1)证明:
平面
;
(2)求二面角
的余弦值大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf469ccdd5d3ea978357af1d60fe4022.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f93f2a12dcd9fd0d4500b26031924404.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88c9167bb3dd30117b6c24fee896a9cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c884b508394b3ab50734b584d9ec783c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c884b508394b3ab50734b584d9ec783c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/24/c03d25b0-e600-4419-82bb-135c4be8189e.png?resizew=326)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/752dc3cc77f0d0ec4a1d0981970410a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6306a5c48c6a2b30eb0c6548c1b99ee.png)
您最近一年使用:0次
名校
解题方法
7 . 如图,在直三棱柱
中,
,
,点
,
分别为
和
的中点,
![](https://img.xkw.com/dksih/QBM/2020/8/14/2527907448750080/2540649089556480/STEM/62142fc7-445c-4499-b9d8-337c37cfd562.png)
(1)求证:
平面
;
(2)求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1baa3d0db9ad31d33c2883a6efed1dc7.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/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://img.xkw.com/dksih/QBM/2020/8/14/2527907448750080/2540649089556480/STEM/62142fc7-445c-4499-b9d8-337c37cfd562.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21dee56b9f36ba8f76fe67b76383636b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb304d905125170bebfada27e7ed8960.png)
您最近一年使用:0次
2020-09-01更新
|
724次组卷
|
2卷引用:重庆市开州区陈家中学2020-2021学年高二上学期10月月考数学试题
名校
解题方法
8 . 如图,四棱锥
的底面
为菱形,
,
底面
,
,E为
的中点.
![](https://img.xkw.com/dksih/QBM/2020/4/27/2450758268633088/2452467380109312/STEM/eac198fef55b422b990422b9d8069a37.png?resizew=177)
(1)求证:
平面
;
(2)求三棱锥
的体积
;
(3)在侧棱
上是否存在一点M,满足
平面
,若存在,求
的长;若不存在,说明理由.
![](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/e075468e7fb0bf30229aec01a7205977.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/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/2020/4/27/2450758268633088/2452467380109312/STEM/eac198fef55b422b990422b9d8069a37.png?resizew=177)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bb178784aa857d4d4683e650273f054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65277734669566578cbb7d690bb200fb.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99e77e93fb69b4c0716dde86f52e7406.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb6eae1bc47c27b6cf8dd4a2cba08db5.png)
(3)在侧棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f1897a7e856b42f8cee0f286ad913d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
您最近一年使用:0次
2020-04-30更新
|
300次组卷
|
2卷引用:重庆市渝北区松树桥中学2020-2021学年高二上学期12月月考数学试题
名校
解题方法
9 . 如图,在平行四边形
中,
,
,
,
分别是
和
的中点,将
沿着
向上翻折到
的位置,连接
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/eed84f19-b7ad-472f-a012-40fb19fc6eef.png?resizew=334)
(1)求证:
平面
;
(2)若翻折后,四棱锥
的体积
,求
的面积
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b96fac11d72f72c805dbddb8da72d68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc3814287dbb60d478bffc5366f9928b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32a07205a2580b2b9f5ca3c3e0920cab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87cdc08e1c4a04a18d5ecea03393e36d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/eed84f19-b7ad-472f-a012-40fb19fc6eef.png?resizew=334)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f62fd0b510920be6bc60d170c3ff3da3.png)
(2)若翻折后,四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72dfcc26700f0801e8113e1caeb4a6eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b345b3acb3453fa84d956718aa5847a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3949cce1b099918ac010dee873c409ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
您最近一年使用:0次
2020-02-16更新
|
383次组卷
|
2卷引用:2019届重庆市南开中学高考冲刺二(文)数学试题
10 . 如图,在三棱柱
中,
,
,
,D是棱BC的中点,E是侧面四边形
的对角线
的中点.
![](https://img.xkw.com/dksih/QBM/2019/11/28/2343720216010752/2394508680888320/STEM/f194f152b5d74224b8cbd6e6071f545c.png?resizew=144)
(Ⅰ)求证:
平面
;
(Ⅱ)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22baaea72c9286f1d8d7b99c37755678.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc0a886f1192d450ced9fd875e78425e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46fe926770d2354e172dec02f5ce2efe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://img.xkw.com/dksih/QBM/2019/11/28/2343720216010752/2394508680888320/STEM/f194f152b5d74224b8cbd6e6071f545c.png?resizew=144)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(Ⅱ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
您最近一年使用:0次