1 . 在立体几何探究课上,老师给每个小组分发了一个正四面体的实物模型,同学们在探究的过程中得到了一些有趣的结论.已知直线
平面
,直线
平面
,F是棱BC上一动点,现有下列四个结论:
①若M,N分别为棱AC,BD的中点,则直线
平面
;
②在棱BC上存在点F,使AF⊥平面
;
③当F为棱BC的中点时,平面
平面
;
④平面
与平面BCD所成锐二面角的正切值为
.
其中所有正确结论的编号是( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/bf1a5652-1840-4be2-afa1-07146d035808.png?resizew=161)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a5edfe97aeab0cf16b40fa9d2e15f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08f8b463fcecf0a757f386db56e074d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
①若M,N分别为棱AC,BD的中点,则直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
②在棱BC上存在点F,使AF⊥平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
③当F为棱BC的中点时,平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d62d30d732c3c6ee3f0dd66d7059356.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
④平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
其中所有正确结论的编号是( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/bf1a5652-1840-4be2-afa1-07146d035808.png?resizew=161)
A.①② | B.①③ | C.②④ | D.③④ |
您最近一年使用:0次
2021-11-28更新
|
542次组卷
|
3卷引用:贵州省毕节市金沙县2022届高三11月月考数学(理)试题
2 . 三棱锥
中,
,
,
,
平面
,
,
为
中点,点
在棱
上(端点除外).过直线
的平面
与平面
垂直,平面
与此三棱锥的面相交,交线围成一个四边形.
![](https://img.xkw.com/dksih/QBM/2021/4/14/2699486354137088/2714328468586496/STEM/98316546-9b2a-4a60-ba1c-7b1fcf71c2ca.png)
(1)在图中画出这个四边形,并写出作法(不要求证明);
(2)若
,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab2c27eac56fffa4cd7dbe1dcdf1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/077c956ac0eb05cf120e14f17413dfa2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://img.xkw.com/dksih/QBM/2021/4/14/2699486354137088/2714328468586496/STEM/98316546-9b2a-4a60-ba1c-7b1fcf71c2ca.png)
(1)在图中画出这个四边形,并写出作法(不要求证明);
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a15e9285ea086558910c16a5127ffb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
您最近一年使用:0次