1 . 在底面为正方形的四棱锥
中,平面
平面
分别为棱
和
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/8e72a2ae-2937-4cc2-bbca-a0ffe5782213.png?resizew=188)
(1)求证:
平面
;
(2)若直线
与
所成角的正切值为
,求平面
与平面
所成锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e07a92153af3a5c755f703a21ec8146f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/8e72a2ae-2937-4cc2-bbca-a0ffe5782213.png?resizew=188)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31f8f7e40ba386c0a9675896b52752d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
2020-01-28更新
|
975次组卷
|
8卷引用:2020年秋季高三数学开学摸底考试卷(新高考)03
(已下线)2020年秋季高三数学开学摸底考试卷(新高考)03(已下线)黄金卷06 【赢在高考·黄金20卷】备战2021年高考数学全真模拟卷(广东专用)(已下线)考点52 空间向量在立体几何中的运用-备战2022年高考数学一轮复习考点帮(新高考地区专用)【学科网名师堂】(已下线)专题22 盘点空间线面角的问题——备战2022年高考数学二轮复习常考点专题突破2020届山东省潍坊市高三上学期期末考试数学试题江苏省苏州市2021-2022学年高三上学期期初调研数学试题江苏省南京市第五中学2021-2022学年高三上学期一模热身数学试题辽宁省大连市第八中学2021-2022学年高二上学期10月阶段考试数学试题
2 . 如图,在三棱柱
中,
平面
,
是
的中点,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/f5589b35-11e9-4836-bf22-b7525c4339de.png?resizew=217)
(Ⅰ)求证:
平面
;
(Ⅱ)求平面
与平面
所成锐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/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3ca0f2b2b40440365fcce22ac32c0ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60d43f4149752473cc6a8ebd29a03608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/f5589b35-11e9-4836-bf22-b7525c4339de.png?resizew=217)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cd597851c0db4e4de4769e10e09383b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
(Ⅱ)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
您最近一年使用:0次
2020-01-24更新
|
1799次组卷
|
4卷引用:专题20 立体几何综合大题必刷100题-【千题百练】2022年新高考数学高频考点+题型专项千题百练(新高考适用)
(已下线)专题20 立体几何综合大题必刷100题-【千题百练】2022年新高考数学高频考点+题型专项千题百练(新高考适用)2020届广东省茂名市高三第一次综合测试数学(理)试题河北省正定中学(实验中学)2019-2020学年高三下学期第三次阶段质量检测数学(理)试题四川省遂宁市射洪中学校2022-2023学年高二强基班上学期第二次半月考数学理科试题
名校
解题方法
3 . 在如图所示的几何体中,四边形
是正方形,四边形
是梯形,
,
,平面
平面
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/4c56edfc-044e-4cca-9645-a6bc3785a0ba.png?resizew=167)
(1)求证:
平面
;
(2)求二面角
的正弦值;
(3)已知点
在棱
上,且异面直线
与
所成角的余弦值为
,求线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c7bce6eba5d07a34f24c5370c580ac7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/133659fd88416259e3b99eaf5751b98d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3025e649f4d4bc6bbda122f940cf8a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16c032261d2f887de100ed40e8fc676e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28ea2d880b20542c2d813f95c683403e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/4c56edfc-044e-4cca-9645-a6bc3785a0ba.png?resizew=167)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e7bcd16691fdd6c2f280ed20a72f2cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e738d31d5d2d20134ed862d404f3fb5d.png)
(3)已知点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/826c728050e3378921442ace20269ef6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de7246b49f9c9b524db7a8929133cb4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7e4fa04825ac7d071968056322d88be.png)
您最近一年使用:0次
2020-05-11更新
|
710次组卷
|
10卷引用:考点26 空间向量求空间角(练习)-2021年高考数学复习一轮复习笔记
(已下线)考点26 空间向量求空间角(练习)-2021年高考数学复习一轮复习笔记【区级联考】天津市部分区2019届高三联考一模数学(理)试题天津市静海一中2019届高三质量调查(一)数学(理)试题2019届天津市部分区高三下学期质量调查(一)数学(理)试题天津市静海区大邱庄中学2020届高三下学期第一次月考数学试题(已下线)2020届天津市北辰区高三第一次诊断测试数学试题天津市武清区杨村一中2019-2020学年高三(下)开学考数学试题天津市第一中学滨海学校2020-2021学年高三上学期12月第三次月考数学试题天津市静海区北师大静海实验学校2024届高三上学期第二次阶段检测数学试题天津市五校联考2023-2024学年高二上学期期中考试数学试题
4 . 如图(1),边长为
的正方形
中,
,
分别为
、
上的点,且
,现沿
把
剪切、拼接成如图(2)的图形,再将
,
,
沿
,
,
折起,使
、
、
三点重合于点
,如图(3).
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/6036a81c-da8b-48be-9c6e-687c673771bf.png?resizew=378)
(1)求证:
;
(2)求二面角
最小时的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a0a24ab1d027cb14725a6a758a6c785.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8414369aceaa4231d66c698380926b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1a2dbe2665ec6a0fadff8e19da12f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8414369aceaa4231d66c698380926b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db5e1441a49e782ff0ef46e776cde06a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c314398e26ffc7164b82946eeb4273.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/6036a81c-da8b-48be-9c6e-687c673771bf.png?resizew=378)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73eb93407a3b472affa1748a1db672e2.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fe90997c0a36e47450b5cbaea013781.png)
您最近一年使用:0次
2020-01-11更新
|
472次组卷
|
3卷引用:专题24 盘点立体几何中折叠问题——备战2022年高考数学二轮复习常考点专题突破
(已下线)专题24 盘点立体几何中折叠问题——备战2022年高考数学二轮复习常考点专题突破山东省德州市2019-2020学年高三上学期期末数学试题江苏省连云港市灌南高级中学2022-2023学年高二下学期第一次月考数学试题
5 . 已知C是以AB为直径的圆周上一点,
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/8120c0af-172b-4146-9a1d-27490408f0ad.png?resizew=190)
(1)求证:平面
平面
;
(2)若异面直线PB与AC所成的为
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ad67d40e34725e0efe62db05bbe27ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/8120c0af-172b-4146-9a1d-27490408f0ad.png?resizew=190)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)若异面直线PB与AC所成的为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/850319b7098a23b859791d7da3e63e74.png)
您最近一年使用:0次
2020-01-10更新
|
478次组卷
|
2卷引用:2020届高三1月(考点07)(理科)-《新题速递·数学》
名校
6 . 如图,在三棱锥
中,已知
都是边长为
的等边三角形,
为
中点,且
平面
,
为线段
上一动点,记
.
![](https://img.xkw.com/dksih/QBM/2020/8/24/2534960207273984/2537454237327360/STEM/8548a81b-a78a-4c35-bccd-63a475cc814d.png)
(1)当
时,求异面直线
与
所成角的余弦值;
(2)当
与平面
所成角的正弦值为
时,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5414bf0f51ceb7f2c3bc9b16cf4ba9c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89673684a25aedb9d800f192bc4291f2.png)
![](https://img.xkw.com/dksih/QBM/2020/8/24/2534960207273984/2537454237327360/STEM/8548a81b-a78a-4c35-bccd-63a475cc814d.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1c3ea872a20fdc1843cb5ffce8a554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2f75c42c77264076166fff76cfab4ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
2020-08-28更新
|
838次组卷
|
8卷引用:【理科附加】专题04 空间点、直线、平面之间的位置关系-2020年高考数学母题题源解密(江苏专版)
(已下线)【理科附加】专题04 空间点、直线、平面之间的位置关系-2020年高考数学母题题源解密(江苏专版)江苏省扬州市2020届高三下学期6月最后一卷数学试题江苏省盐城市滨海县八滩中学2020届高三下学期高考模拟考试(二)数学试题江苏省邗江中学2017-2018学年高二下学期期中考试数学(理)试题江苏省泰州市泰州中学2018-2019学年高二下学期期中考试数学(理)试题福建省三明第一中学2019-2020学年高二上学期期中考试数学试题(已下线)【新东方】杭州新东方高中数学试卷328(已下线)第一章 空间向量与立体几何 单元测试-2023-2024学年高二数学同步精品课堂(人教B版2019选择性必修第一册)
7 . 如图,在四棱锥
中,
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c707f0202ec1aa233e1eeacc7a4587d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fbc98fa18c1c08c88c95b15aee6d6bf.png)
,
为线段
上一点不在端点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/0b75dba1-b8be-435a-8e47-e736fde06d9b.png?resizew=193)
(1)当
为中点时,
,求证:
面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0cbbcc3d79bf999588882e7b1b4324.png)
(2)当
为
中点时,是否存在
,使得直线
与平面
所成角的正弦值为
,若存在求出M的坐标,若不存在,说明理由.
![](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/9c707f0202ec1aa233e1eeacc7a4587d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fbc98fa18c1c08c88c95b15aee6d6bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/685f60234c313fba13f5d706372b788b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62794ea73abc2a84aa0512c5b205eb12.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/0b75dba1-b8be-435a-8e47-e736fde06d9b.png?resizew=193)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bb9d08376d152bf4deed8b7e266b7fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02438f0423acd0ff2dfa5ffb6abf143f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0cbbcc3d79bf999588882e7b1b4324.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
您最近一年使用:0次
2020-01-09更新
|
1438次组卷
|
5卷引用:卷05-备战2020年新高考数学自学检测黄金10卷-《2020年新高考政策解读与配套资源》
(已下线)卷05-备战2020年新高考数学自学检测黄金10卷-《2020年新高考政策解读与配套资源》吉林省长春市榆树市2019-2020学年高二上学期期末数学(理)试题浙江省杭州“六县九校”联盟2021-2022学年高二下学期期中联考数学试题湖北省重点高中智学联盟2021-2022学年高二下学期5月联考数学试题安徽省六安市舒城中学2021-2022学年高二下学期期中数学试题
8 . 如图,梯形
中,
,
,
,
、
分别是
,
的中点,现将
沿
翻折到
位置,使![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b58bbc02479917ad761a24eaae0dbfd9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/1/3eac3639-02f7-4695-872b-5b3cd6d2beef.png?resizew=386)
(1)证明:
面
;
(2)求二面角
的平面角的正切值;
(3)求
与平面
所成的角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e696e967e7e6c52f95564261bb21cf44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abbd0617743bc2cb866bdf8bbc78be20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d720f70ec3db9b93472a7360ab6c694e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a6e2867f32d3f1c3cd36cd3a11a8580.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89def28bc64bf40c3607d1fb39437b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc00e548637370b129076f633aae654.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b58bbc02479917ad761a24eaae0dbfd9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/1/3eac3639-02f7-4695-872b-5b3cd6d2beef.png?resizew=386)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d682fd0344452998187cb6d48de3dd1.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
您最近一年使用:0次
解题方法
9 . 如图,在四棱锥
中,底面
为直角梯形,
,
,平面
底面
,
为
的中点,
是棱
上的点且
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/4a501a81-aecb-46d5-94b6-3d3f3fbf5a2a.png?resizew=215)
求证:平面
平面以
;
求二面角
的大小.
![](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/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90ff6d7dd48b57f03d82d2c522ee9b94.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/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1b79bf9d502660aff58cec76863e610.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8254b52b379a420c17d38334940b073.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5729dd997ea7e8cb4cef8b7165b36e00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/792fdb02a063b077df2276235ef2e334.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/4a501a81-aecb-46d5-94b6-3d3f3fbf5a2a.png?resizew=215)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf6c84731e5e1bd335ecfc2d36c3d81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/845b8505cb7b7b8df5753f52a4e00462.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f53190d6ead827a6338b9de847aeaf1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a773fe6d12311dc321198697eb528ba.png)
您最近一年使用:0次
名校
解题方法
10 . 如图的虚线网格纸上小正方形的边长为1,粗实线画出的是某几何体的三视图.在该几何体的直观图中,直线
与
所成角的余弦值为( )
![](https://img.xkw.com/dksih/QBM/2020/2/12/2397569787617280/2398867649388544/STEM/44e3a3fb-c39d-4a59-8295-49617b96307e.png?resizew=260)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/2020/2/12/2397569787617280/2398867649388544/STEM/44e3a3fb-c39d-4a59-8295-49617b96307e.png?resizew=260)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次