1 . 如图,四棱锥
中,底面
为矩形,
平面
,
,点
为
的中点,点
在棱
上移动.
(1)当点
为
的中点时,试判断
与平面
的位置关系,并说明理由;
(2)求证:无论点
在
的何处,都有
;
(3)求二面角
的余弦值.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e909874462678ca750118efdf61a9a98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
(1)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)求证:无论点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6c66902c5f7d00de2e4ba9ccfcfd759.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42f4096ff62b4f29932cd8c6eef661a3.png)
![](https://img.xkw.com/dksih/QBM/2018/1/6/1854389430263808/1854666441711616/STEM/196ecfbecae842cdb0c4a5fa6cc83992.png?resizew=343)
您最近一年使用:0次
2 . 在如图所示的几何体中,四边形
是正方形,
平面
,
分别为
的中点,且
.
![](https://img.xkw.com/dksih/QBM/2017/3/3/1635734485401600/1635910460702720/STEM/68bc0ad244c64227b335d6a4297567d1.png?resizew=196)
(1)求证:平面
平面
;
(2)求证:平面
平面
;
(3)求三棱锥
与四棱锥
的体积之比.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/821f8dbb1df39a1aa3070af00c8fb044.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/308f5a2ad097843999e6d9e68d6cf022.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52ae89f94a73f32a4ed3b138bea550ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e096b55732175ddd58f851903b87dc65.png)
![](https://img.xkw.com/dksih/QBM/2017/3/3/1635734485401600/1635910460702720/STEM/68bc0ad244c64227b335d6a4297567d1.png?resizew=196)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/827af56c71c49a224f75f59e4ffbf71a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea538365f9a15deeea31f87a5d745b4e.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c82799f3333a3a8c9659935fb9902726.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dda09fb28b8f1e165715cca61d64f9c1.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff73b7f5d154b2f7a1962c26841624fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d02bd5cfe804460846423e77f72db10f.png)
您最近一年使用:0次
2017-03-03更新
|
3215次组卷
|
2卷引用:2016-2017学年安徽省六安市第一中学高一上学期周末作业(十三)数学试卷