如图,在四棱锥
中,四边形
为平行四边形,
为边长为2的等边三角形,O为
的中点,
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/3739b78b-2433-48f1-92a3-b1b93744c11f.png?resizew=185)
(1)求证:
;
(2)当四边形
为菱形时,求
与平面
所成角大小的正弦值.
![](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/7a855335176fc36a15017f50a8561348.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7b7675ff57bdccb95a8241c1cd09f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a4d781525777c7b5284dffc70b2a28a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/3739b78b-2433-48f1-92a3-b1b93744c11f.png?resizew=185)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55c5c1737061bd9da03897a79e7b243f.png)
(2)当四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
更新时间:2020-03-26 07:26:12
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】如图,在多面体ABCDEF中,正方形
与梯形
所在平面互相
垂直,已知
,
,
.
![](https://img.xkw.com/dksih/QBM/2015/7/9/1572175742091264/1572175748251648/STEM/ce3bf7a6662f43a88715b7f4a4d0526d.png)
(Ⅰ)求证:
平面
;
(Ⅱ)求直线
与平面
所成的角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
垂直,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/899389400366ef131e169847a4286301.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d262480ffb55b7617f44b63f130c154a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/833cfda415649b832cc136caed392753.png)
![](https://img.xkw.com/dksih/QBM/2015/7/9/1572175742091264/1572175748251648/STEM/ce3bf7a6662f43a88715b7f4a4d0526d.png)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc3719c11b0b0ae54d43d6f45fe7b1f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(Ⅱ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc3719c11b0b0ae54d43d6f45fe7b1f8.png)
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解答题-证明题
|
较难
(0.4)
【推荐2】如图,平面
平面
,四边形
是边长为2的正方形,
为
上的点,且
平面
.
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/ad9a2c2bcf0447979ff890a6006e9580.png)
(1)求证
平面
;
(2)设
,是否存在
,使二面角
的余弦值为
?若存在,求
的值;若不存在,说明理由.
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/7218758b76ae4484b7c6f0061db1df24.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/2de9d05f67674f2b802fdd0c25975319.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/b4101d92f11c49a18eccae2ccffab0f3.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/41a8906a499743d7974e6a12065ab0a5.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/3588ba6a66b14590b05648b1e7fd418f.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/a242ba8dcdde4f5c99eb81820bf6a01a.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/001b6c00aa594ff99b8c975e8bc0a8f8.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/ad9a2c2bcf0447979ff890a6006e9580.png)
(1)求证
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/7ebf41d6bcd24611af73e428c20a9f72.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/9e14e57bc51347debeb2580647088ea2.png)
(2)设
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/f45052a479854c18946472b7fa7c0f56.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/3acf403700864d55a3deb30327c84c14.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/5fc63902735d4dcdbb324781843be0fe.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/e8ac173a9f6843ca94b227706880a397.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470454476800/1572470460145664/STEM/3acf403700864d55a3deb30327c84c14.png)
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名校
【推荐1】如图,在四棱锥
中,底面ABCD是平行四边形,
是边长为2的正三角形,平面
平面ABCD,
,
,S为CD的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/25/e57b71a9-d739-4ca5-a9b2-a6d9a2814a26.png?resizew=205)
(1)求证:
;
(2)若M是PB的中点,求直线MD与平面ACP所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6be2b61f4a38e2ee2c1a01e00b3ae6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e8f99467f791344ee3306c3ee95ced0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7d7202543c2936a753cfad3ab31f129.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f3178ab6bd13e4c36a29539fd65081d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8bb1ebb034e48ae054c737e53e1812a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/25/e57b71a9-d739-4ca5-a9b2-a6d9a2814a26.png?resizew=205)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2460a1743095444aef0a3e882cb60237.png)
(2)若M是PB的中点,求直线MD与平面ACP所成角的正弦值.
您最近一年使用:0次
解答题-证明题
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较难
(0.4)
名校
解题方法
【推荐2】如图,四棱锥
的底面
是菱形,点
分别在棱
上,
.
平面
;
(2)若二面角
大小为120°,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cf33d73483c93f24cc6a1d76ef22ca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d5c1da4b476133c0d04f66d72cf2535.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6edc42859068e6f83f7c591cca953b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a779876cdfb2c489ad0eaed0f73e6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/213d25b5ade550ec6afd3536e9eb5d75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
您最近一年使用:0次