名校
解题方法
1 . 如图所示的几何体为一个正四棱柱被两个平面
与
所截后剩余部分,且满足
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/1477b758-6170-42d8-b055-c1aacdcbecac.png?resizew=185)
(1)当
多长时,
,证明你的结论;
(2)当
时,求平面
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72406478fda1c6e3b8052467385a3bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09219dbd440c70d66bf2bf8b4c2bfe2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46264ad39c95ef05658e3fa15373c6d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d37cb657446616b7d679dfd9d2bbef5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2743a47b0c3e422512b4c76cc7112232.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/1477b758-6170-42d8-b055-c1aacdcbecac.png?resizew=185)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e79216c6a32bb699aeb36144da020490.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51bb339ba41929e8f693b3618d5ee4b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72406478fda1c6e3b8052467385a3bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09219dbd440c70d66bf2bf8b4c2bfe2f.png)
您最近一年使用:0次
2023-03-10更新
|
923次组卷
|
4卷引用:吉林省长春市长春吉大附中实验学校2023-2024学年高二上学期9月月考数学试题
2 . 如图,将边长为
的等边三角形
沿与边
平行的直线
折起,使得平面
平面
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/c2c5fc03-94dd-446e-a6fc-363ebb539b70.png?resizew=156)
(1)求平面
与平面
所成角的余弦值;
(2)若
平面
,试求折痕
的长;
(3)当点
到平面
距离最大时,求折痕
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6501f1c913a4ef64957a2f01ab5baa15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b312dab930cbbb9a4bb1a99f044dab73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/c2c5fc03-94dd-446e-a6fc-363ebb539b70.png?resizew=156)
(1)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee4a6b8ef3e79b4482388c3391d8b18.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662698361c6b3ddaf0c28a3c87be53e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ed01d1ff5a7f21a68fb3a1e5c7f393e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
(3)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
您最近一年使用:0次
2021-09-30更新
|
221次组卷
|
2卷引用:吉林省长春外国语学校2021-2022学年高二上学期第一次月考数学试题