1 . 如图,在三棱锥
中,平面
平面
,点
为
的重心,
.
平面
,求
的长度;
(2)当
时,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/666e154cbea71fa13440a81dbfa002c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c025ee3317be1099b7bf03a11e37ed4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db1bc3b9a65b6ebe9c0d9cf4f6a0ef44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84b859ca54ab085edf70c1179a7d103a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73b3cf0f585938ede9eca890a6eb326d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
您最近一年使用:0次
2024-06-03更新
|
666次组卷
|
3卷引用:江西省重点中学协作体2024届高三第二次联考数学试卷
名校
解题方法
2 . 如图,在正四棱锥
中,
分别是
的中点,当点
在线段
上运动时,下列四个结论:
;②
;③
平面
;④
平面
.
其中恒成立的为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f77e5821b24a76c71fdc2cf59fbba308.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2da7e82d92b75660d271586a57e931f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc8ccede05f9270d0f04a9545636790.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d1aba56e04a373cefa813b31a3d99f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3834a4bb20d2b065695dbf53091b065.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5000fea066102e62cf2128ccbbd2b3e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4862958e60c245dc9a5d9cb57d31eb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc6f6dfdbe7d39891c35f67e1a95c7f.png)
其中恒成立的为( )
A.①③ | B.③④ | C.①② | D.②③④ |
您最近一年使用:0次
2024-06-03更新
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1378次组卷
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27卷引用:江西省南康中学、于都中学2017-2018学年高二上学期第四次联考数学(理)试题
江西省南康中学、于都中学2017-2018学年高二上学期第四次联考数学(理)试题湖南省株洲市醴陵第二中学、醴陵第四中学2018届高三上学期两校期中联考数学(理)试题【校级联考】江西省南昌八中、二十三中、十三中2018-2019学年高二下学期期中考试数学文科试题2017届四川省成都市石室中学高三二诊模拟考试数学(理)试卷2017届四川省成都市石室中学高三二诊模拟考试数学(文)试卷河北省石家庄二中2020届高三(3月份)高考数学(文科)热身试题2020届河北省衡水市枣强中学高三下学期3月模拟2数学(文)试题江西省部分学校2022-2023学年高三上学期11月质量检测巩固卷理科数学试题黑龙江省鹤岗市第一中学2016-2017学年高一下学期期末考试数学(文)试题黑龙江省鹤岗市第一中学2016-2017学年高一下学期期末考试数学(理)试题宁夏育才中学2018届高三第四次月考数学(理)试题(已下线)7-4 直线、平面平行的判定及其性质(高效训练)-2019版导学教程一轮复习数学(人教版)人教A版 全能练习 必修2 第二章+本章能力测评(二)浙江省宁波市六校联考2019-2020学年上学期高二期中数学试题甘肃省兰州大学附中2017-2018学年高一上学期期末数学试题人教A版(2019) 必修第二册 突围者 第八章 综合拓展提升云南省昭通市昭阳区建飞中学2018-2019学年高二下学期期末数学(文)试题河北省石家庄市第二中学2020届高三下学期3月内部考试数学(文)试题四川省内江市第六中学2020-2021学年高三上学期第三次月考数学(文)试题(已下线)第33练 立体几何的综合-2021年高考数学(文)一轮复习小题必刷安徽省安庆市桐城市第八中学2020-2021学年高二上学期期初检测数学试题人教A版(2019) 必修第二册 实战演练 第八章 验收检测(已下线)第8章 立体几何初步(单元基础卷)-2021-2022学年高一数学考试满分全攻略(人教A版2019必修第二册)广东省深圳市第二十二高级中学(中科附高)2023-2024学年高二上学期开学考试数学试题(已下线)第八章 本章综合--方法提升应用【第三练】“上好三节课,做好三套题“高中数学素养晋级之路(已下线)6.5.1直线与平面垂直-【帮课堂】(北师大版2019必修第二册)(已下线)第六章 立体几何初步(单元测试,新题型)-同步精品课堂(北师大版2019必修第二册)
名校
3 . 如图,在三棱柱
中,平面
平面
,
,过
的平面与
分别交于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/14/9cfa1401-dba7-4adf-8ade-288c789e11a6.png?resizew=174)
(1)证明:四边形
为平行四边形;
(2)若
,则当
为何值时,直线
与平面
所成角的正弦值最大?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eff0db05826cbff651faf0144904b32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/665d44844d2b582e965128979a6f7091.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ba9574b2a856772570046d87a6242be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8db1db021a0cb0c7f301f6760258689d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0ae07505d28385b5ae7fa6769e6f91b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/14/9cfa1401-dba7-4adf-8ade-288c789e11a6.png?resizew=174)
(1)证明:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebb05874eb3353d754af24c9974273e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35e2d45fd8c3d3d809571ce6d3b81271.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebb05874eb3353d754af24c9974273e.png)
您最近一年使用:0次
2024-04-10更新
|
995次组卷
|
3卷引用:江西省南昌市第十九中学2024届高三下学期第二次模拟考试数学试题
解题方法
4 . 一年一度的创意设计大赛开幕了.今年小王从世界名画《永恒的记忆》中获得灵感,创作出了如图1的《垂直时光》.已知《垂直时光》是由两块半圆形钟组件和三根指针组成的,它如同一个标准的圆形钟沿着直径
折成了直二面角(其中
对应钟上数字3,
对应钟上数字9).设
的中点为
,若长度为2的时针
指向了钟上数字8,长度为3的分针
指向了钟上数字12.现在小王准备安装长度为3的秒针
(安装完秒针后,不考虑时针与分针可能产生的偏移;不考虑三根北针的粗细).
(1)若秒针
指向了钟上数字4,如图2.连接
、
,若
平面
.求半圆形钟组件的半径;
(2)若秒针
指向了钟上数字5,如图3.设四面体
的外接球球心为
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.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/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/26/9bc32e01-aae0-45c8-bdf6-e78ec83f4bf8.png?resizew=498)
(1)若秒针
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c023f4b501684abd869b36d6e6c7f21f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6fe3ee05321860442e84d54c6f328b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb802b0cd77d772dceff0d9ff6c879ac.png)
(2)若秒针
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3241d7fedd89d85711acd7a2635298af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7303d343202b6444bb0ccff94e48e7c.png)
您最近一年使用:0次
5 . 如图,三棱锥中,底面
与侧面
是全等三角形,侧面
是正三角形,
,
,
,
,
,
,
分别是所在棱的中点,平面
与平面
相交于直线
.
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/917d1dcd19fe8825c952c25d46fb778b.png)
(2)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
您最近一年使用:0次
名校
解题方法
6 . 如图,在四棱锥P-ABCD中,底面ABCD为平行四边形,
,
,
,
,
,点N在棱PC上,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/d722ce18-c51c-4659-981c-791da93210f8.png?resizew=184)
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9e5f1cfea3643c30c21732073a11ef.png)
(2)若
平面BDN,求平面
与平面
所成夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e918b70b02a73685e3c536c7f380e2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3ad66112b09c909cab417085702ec00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37002ada5d194d4d062fa3285d7d9824.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b235d0737ddc0d2c85abd4484c10d76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/d722ce18-c51c-4659-981c-791da93210f8.png?resizew=184)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9e5f1cfea3643c30c21732073a11ef.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6684d8fe0d6da7564247e47b948e3997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b81f4392b5d212943995024ff480d175.png)
您最近一年使用:0次
2023-05-02更新
|
364次组卷
|
2卷引用:江西省景德镇市2023届高三第二次质检试题数学(理)试题
名校
解题方法
7 . 如图,在四棱锥
中,
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/77f0ef14-6bcd-4653-9638-91b27200afd9.png?resizew=226)
(1)若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
平面
,证明:点
为棱
的中点;
(2)已知二面角
的大小为
,当平面
和平面
的夹角为
时,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0998d16d7bf13acae5bfb9b8de55ca04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d5ff57f147aa0628fdd47899b5a132.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/77f0ef14-6bcd-4653-9638-91b27200afd9.png?resizew=226)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
(2)已知二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f479b251fdb01bae6d16abb7f2d694a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d5bca00fa20e6e80480b9d06d2e52ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6943f158bf2f76abed0c58196dbe0bc5.png)
您最近一年使用:0次
2023-04-10更新
|
469次组卷
|
3卷引用:江西省吉安市2023届高三模拟测试数学(理)(一模)试题
名校
解题方法
8 . 在四棱锥
中,底面
为梯形,
,
,点
在侧棱
上,点
在侧棱
上运动,若三棱锥
的体积为定值,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05743bf71c3e77faa60358f88978f934.png)
_____
![](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/12143a06ed24558d8cc7ad39961d3e1f.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/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92a8f6da9a92a1c578cbbc52a44fcff4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05743bf71c3e77faa60358f88978f934.png)
您最近一年使用:0次
2023-03-24更新
|
707次组卷
|
7卷引用:江西省南昌市2023届高三第一次模拟测试数学(理)试题
江西省南昌市2023届高三第一次模拟测试数学(理)试题四川省绵阳市绵阳中学2023届高三高考模拟理科数学试题(四)(已下线)专题13立体几何(选择填空题)广西壮族自治区防城港市2023届高三下学期4月月考数学(理)试题四川省绵阳市绵阳南山中学实验学校2022-2023学年高三下学期4月月考数学理科试题(已下线)考点17 立体几何中的定值问题 2024届高考数学考点总动员【练】(已下线)考点17 立体几何中的定值问题 2024届高考数学考点总动员【讲】
解题方法
9 . 如图,在四棱锥
中,底面
为平行四边形,
,
,
,
,
,点
在棱
上,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/5e14cec5-6138-4131-8a53-d89d8d8644bb.png?resizew=193)
(1)证明:
;
(2)若
平面
,求三棱锥
的体积.
![](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/7e918b70b02a73685e3c536c7f380e2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3ad66112b09c909cab417085702ec00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37002ada5d194d4d062fa3285d7d9824.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b235d0737ddc0d2c85abd4484c10d76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/5e14cec5-6138-4131-8a53-d89d8d8644bb.png?resizew=193)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9e5f1cfea3643c30c21732073a11ef.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfaf581b4f42a25087f7eee23a7d66b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5a94e7ab62cf6374d2e4c6d7240a271.png)
您最近一年使用:0次
名校
解题方法
10 . 如图,正三棱柱
中,
分别是棱
,
上的点,
平面
,且M是AB的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/17/5cf17122-cce0-48ff-80cc-bcb365818b82.png?resizew=160)
(1)证明:平面
平面
;
(2)若
,求平面BEF与平面BCE夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b96dce1ec94eb90c243b2eddb78476.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa14afe6f0aad22e8e869c39a60be657.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/17/5cf17122-cce0-48ff-80cc-bcb365818b82.png?resizew=160)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e51838e395dfc9d9ef597d9e01f46272.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06a2ab6940dca62be1f3b2b5f8531990.png)
您最近一年使用:0次
2022-11-14更新
|
699次组卷
|
3卷引用:江西省景德镇市2023届高三上学期第一次质检试题数学(理)试题