名校
解题方法
1 . 如图,在边长为2的正方形
中,点
是边
的中点,将
沿
翻折到
,连结
,
,在
翻折到
的过程中,下列说法正确的是_________ .(将正确说法的序号都写上)
的体积的最大值为
;
②当面
平面
时,二面角
的正切值为
;
③存在某一翻折位置,使得
;
④棱
的中点为
,则
的长为定值.
![](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/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7f9fba8a4098c1a0515286eb8d616dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb62dd4766d11cfec3aee092b99e40c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7f9fba8a4098c1a0515286eb8d616dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb62dd4766d11cfec3aee092b99e40c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec53c9cc69c2e3943ec8df5d5b5d44c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
②当面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392469b357b12b998528499929366c02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760712e3e2ea02b755b751e760d0c55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47d294d69caac577339f11f477b2047e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59d2d267caf23c33bf34f6e2764ada9c.png)
③存在某一翻折位置,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0efbdc4cbc82cc55bed9905f81fbfc2.png)
④棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167d31eb8432b5c0364316e5048c23dd.png)
您最近一年使用:0次
2021-12-10更新
|
1090次组卷
|
3卷引用:黑龙江省哈尔滨师范大学附属中学2021-2022学年高三上学期期中考试数学(理)试题
黑龙江省哈尔滨师范大学附属中学2021-2022学年高三上学期期中考试数学(理)试题(已下线)第八章 立体几何初步(提分小卷)-【单元测试】2021-2022学年高一数学尖子生选拔卷(人教A版2019必修第二册)福建省浦城第一中学2023-2024学年高一下学期4月期中考试数学试题
名校
解题方法
2 . 已知正方体
内切球的表面积为
,
是空间中任意一点:
①若点
在线段
上运动,则始终有
;
②若
是棱
中点,则直线
与
是相交直线;
③若点
在线段
上运动,三棱锥
体积为定值;
④
为
中点,过点
,且与平面
平行的正方体的截面面积为
;
以上命题为真命题的个数为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70f5389990c3a0c5373f3bd9fb2454c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
①若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/763be97fe1e030b5509bda231a546001.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
③若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a80afb14665ad9cb3587c5364980e30.png)
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923189afc198d153c79059a827f63c87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/839c7616cd0d90265f4b2c9c021254fe.png)
以上命题为真命题的个数为( )
A.2 | B.3 | C.4 | D.5 |
您最近一年使用:0次
名校
3 . 如图,在四棱锥
中,四边形
是等腰梯形,
.
分别是
的中点,且
,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/1cbf98ad-109a-4488-bdc9-c09e898e3008.png?resizew=190)
(1)证明:
平面
;
(2)已知三棱锥
的体积为
,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/2e263d46c107fa79a457b642ba035340.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7490886e2807c7b8a4fa57d99c4dc3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9df7fc746f8c4801d8f2f0471ba3297e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/397dab2cc39244e41e1744214cccb204.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/1cbf98ad-109a-4488-bdc9-c09e898e3008.png?resizew=190)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)已知三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63cd98983166c6f861b82f45bff0e179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c764736ec31656bbd4fe87ca8a593506.png)
您最近一年使用:0次
2021-03-23更新
|
705次组卷
|
5卷引用:黑龙江省七台河市勃利县高级中学2021-2022学年高二上学期9月月考数学试题