名校
1 . 如图,多面体ABCDEF中,DE⊥平面ABCD,底面ABCD是菱形,AB=2,∠BAD=60°,四边形BDEF是正方形.
![](https://img.xkw.com/dksih/QBM/2021/11/19/2854712830689280/2857331093274624/STEM/7aa19aee-ce29-46f3-b057-822b4ac118c0.png?resizew=258)
(1)求证;CF∥平面AED;
(2)求直线AF与平面ECF所成角的正弦值.
![](https://img.xkw.com/dksih/QBM/2021/11/19/2854712830689280/2857331093274624/STEM/7aa19aee-ce29-46f3-b057-822b4ac118c0.png?resizew=258)
(1)求证;CF∥平面AED;
(2)求直线AF与平面ECF所成角的正弦值.
您最近一年使用:0次
2021-11-23更新
|
314次组卷
|
4卷引用:安徽省宿州市砀山中学2021-2022学年高二上学期第一次质量检测数学试题
名校
2 . 如图,已知
为正三角形,D为AB的中点,E在AC上,且
,现沿DE将
折起,折起过程中点A仍然记作点A,使得平面
平面BCED,在折起后的图形中.
![](https://img.xkw.com/dksih/QBM/2021/9/13/2807128439554048/2815225309601792/STEM/80d94deb-2f09-4c04-872f-88daac4f7a21.png?resizew=472)
(1)在AC上是否存在点M,使得直线
平面ABD.若存在,求出点M的位置;若不存在,说明理由.
(2)求平面ABD与平面ACE所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb8f6c9335373be2e09046a1e51424f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d28c625d7ac6878957facc8274d459c.png)
![](https://img.xkw.com/dksih/QBM/2021/9/13/2807128439554048/2815225309601792/STEM/80d94deb-2f09-4c04-872f-88daac4f7a21.png?resizew=472)
(1)在AC上是否存在点M,使得直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6dfed58659a9cab4d1836c3d2effdc.png)
(2)求平面ABD与平面ACE所成锐二面角的余弦值.
您最近一年使用:0次
2021-09-24更新
|
526次组卷
|
2卷引用:安徽省宿州市砀山中学2021-2022学年高二上学期第一次质量检测数学试题
名校
解题方法
3 . 如图在
中,点
,
分别在线段
,
上,且
,
,
.若将
沿
折起到
的位置,使得
.
![](https://img.xkw.com/dksih/QBM/2020/11/23/2599038707851264/2603262269874176/STEM/8abf004ed7c94d15a735f7e0ba5bfb60.png?resizew=371)
(1)求证:平面
平面
;
(2)在棱
上是否存在点
,使得
平面
?说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e987ef5b2677d3b860a9882770ac718.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff84ae2da2c81b5c7ccb7e52b40eff6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98013a5042685a1db94249e70c62c09a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1ed4c4e8edbd179f3fc38a6653f18c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edf0b97ff7e422ab6ecdceec4126ede1.png)
![](https://img.xkw.com/dksih/QBM/2020/11/23/2599038707851264/2603262269874176/STEM/8abf004ed7c94d15a735f7e0ba5bfb60.png?resizew=371)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d032cd687ca6075a3f5708c5d2bec01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7af6b531f532eb39c26d36e9dd97254d.png)
(2)在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deb9c174c70bd93bb9fea871fc2c23d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03203dd5ac79dd8c6707e4340773359.png)
您最近一年使用:0次
2020-11-29更新
|
219次组卷
|
2卷引用:安徽省宿州市十三所重点中学2020-2021学年高二上学期期中联考数学(文)试题