名校
1 . 在四棱锥
中,
,
,
,
,
为正三角形,且平面
平面ABCD.
![](https://img.xkw.com/dksih/QBM/2022/1/14/2894422649323520/2897144021975040/STEM/68d32b3d-3e68-4d14-a0a8-b707d27d9339.png?resizew=192)
(1)求二面角
的余弦值;
(2)线段PB上是否存在一点M(不含端点),使得异面直线DM和PE所成的角的余弦值为
?若存在,指出点M的位置;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4622847599656e5684350af7e60f0d20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea4f5eec0addba78f2e0cdfb7ecc59a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c45087cde2d66377517a3fce5553b35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://img.xkw.com/dksih/QBM/2022/1/14/2894422649323520/2897144021975040/STEM/68d32b3d-3e68-4d14-a0a8-b707d27d9339.png?resizew=192)
(1)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df6aaed07f0b69eee41de11613fc74de.png)
(2)线段PB上是否存在一点M(不含端点),使得异面直线DM和PE所成的角的余弦值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaa42621cd6793e7f3673fdb49bc3123.png)
您最近一年使用:0次
2022-01-18更新
|
2099次组卷
|
4卷引用:内蒙古包头市2021-2022学年高二上学期期末考试数学(理)试题
内蒙古包头市2021-2022学年高二上学期期末考试数学(理)试题(已下线)江苏省南通市如皋市2021-2022学年高二下学期期初调研数学试题内蒙古呼和浩特市新城区呼市十四中学2023-2024学年高二上学期期中数学试题(已下线)专题03 空间向量求角度与距离10种题型归类-【巅峰课堂】2023-2024学年高二数学上学期期中期末复习讲练测(人教A版2019选择性必修第一册)
名校
2 . 如图,在四棱锥
中,底面
中
,
,侧面
平面
,且
,点
在棱
上,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/22/29abe2ad-3248-4320-95f7-063435bc37e4.png?resizew=198)
(Ⅰ)证明:
平面
;
(Ⅱ)求二面角
的余弦值
![](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/3402ea855e2ae2dcd98f607bef4fdd6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5f0cfc1049f84a04c81bd213afb8d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4770a1f98495ff85859bc6508d6d5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76b54647a7c34d1046c8d6c198d3654d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/22/29abe2ad-3248-4320-95f7-063435bc37e4.png?resizew=198)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11d27ff0b39832f094ec51e28721d739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
(Ⅱ)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/135a12aa48eb33bf5116662e0f9f0799.png)
您最近一年使用:0次
2020-11-24更新
|
1029次组卷
|
4卷引用:内蒙古赤峰红旗中学2021-2022学年下学期高二年级期中考试数学试题
内蒙古赤峰红旗中学2021-2022学年下学期高二年级期中考试数学试题天一大联考(河北广东全国新高考)2020—2021 学年高中毕业班阶段性测试(二)(已下线)第八单元 立体几何 (A卷 基础过关检测)-2021年高考数学(理)一轮复习单元滚动双测卷广西南宁市2021届高三12月特训测试理科数学试题