名校
1 . 如图,四边形ABCD为梯形,
,
,
,点
在线段
上,且
.现将
沿
翻折到
的位置,使得
.
![](https://img.xkw.com/dksih/QBM/2022/3/2/2927482149060608/2936643822362624/STEM/f93ceca9-e75b-4c76-b3e0-ff9295997956.png?resizew=251)
(1)证明:
;
(2)点
是线段
上的一点(不包含端点),是否存在点
,使得二面角
的余弦值为
?若存在,则求出
;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/998329f9cdb86f5d60d7d5d70fc3781e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86752e4373797b2231f76b074cbf75d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b937442ad4cc480adc11bb143559454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbe40405cd7bd60d69dd535d6da85c00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fbb42439079fa563100decbad833e10.png)
![](https://img.xkw.com/dksih/QBM/2022/3/2/2927482149060608/2936643822362624/STEM/f93ceca9-e75b-4c76-b3e0-ff9295997956.png?resizew=251)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbfbaf73297240eb116f22489519895a.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98553247801c03de24cf7e687016e655.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174142f3bba761585b6bc2653009b36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad0d6d600e2676abc87e05cde8aebc1a.png)
您最近一年使用:0次
2022-03-15更新
|
3289次组卷
|
9卷引用:重庆市荣昌中学校2022-2023学年高二上学期第一次月考数学试题