名校
1 . 已知梯形
和矩形
. 在平面图形中,
,
. 现将矩形
沿
进行如图所示的翻折.
![](https://img.xkw.com/dksih/QBM/2022/4/28/2967945479561216/2969215240691712/STEM/c0c1898ca2ec48ac93df4cbb5ebc9602.png?resizew=318)
(1)当二面角
的大小为
时.求
的长;
(2)设
是
中点.
①当二面角
的大小为
时,若
,且点
在平面
内,求实数
的值;
②求在翻折的过程中,直线
与平面
所成最大角的正弦值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b0bba92628a9b45cbba7721fc7e7722.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7dac702fe64edf1bc265da4b98cf2a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/2022/4/28/2967945479561216/2969215240691712/STEM/c0c1898ca2ec48ac93df4cbb5ebc9602.png?resizew=318)
(1)当二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1d76403bac26df50d934d93586f8a11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f785147690f83dcee0a0bc6c327e75a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
①当二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1d76403bac26df50d934d93586f8a11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1ad72d7565699d1ebb741eb0ce12bac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5a4d4cb32d487bac08764b2b4992e41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
②求在翻折的过程中,直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
您最近一年使用:0次
2022-04-30更新
|
302次组卷
|
2卷引用:福建省三明市第二中学2022-2023学年高二上学期开学适应性练习数学试题
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解题方法
2 . 如图,在平面直角坐标系
中,点
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/1/20/2898435970957312/2921487903080448/STEM/e19f691312ab43468e61f2af0ec17e98.png?resizew=167)
(1)求直线BC的方程;
(2)记
的外接圆为圆M,若直线OC被圆M截得的弦长为4,求点C的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/448c0a5ee776d19ce8e42ac9a5fd27c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f455353f09b4c255f8a5efeb72b9e93c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae5a64bcb77f5f64e4af6930c249a270.png)
![](https://img.xkw.com/dksih/QBM/2022/1/20/2898435970957312/2921487903080448/STEM/e19f691312ab43468e61f2af0ec17e98.png?resizew=167)
(1)求直线BC的方程;
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe95f656b98b53f71a9d72bf0c9a4b9.png)
您最近一年使用:0次
2022-02-22更新
|
500次组卷
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4卷引用:福建省三明市永安第九中学2022-2023学年高二下学期返校考试数学试题
3 . 如图的一系列正方形图案称为谢尔宾斯基地毯,图案的做法是:把一个正方形分成9个全等的小正方形,对中间的一个小正方形进行着色得到第1个图案(图1);在第1个图案中对没有着色的小正方形再重复以上做法得到第2个图案(图2);以此类推,每进行一次操作,就得到一个新的正方形图案,设原正方形的边长为1,记第n个图案中所有着色的正方形的面积之和为
,则数列
的通项公式![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
![](https://img.xkw.com/dksih/QBM/2022/1/20/2898435970957312/2921487902916608/STEM/fd497271-2f51-4dae-81a1-5d8cda66c50d.png?resizew=464)
您最近一年使用:0次
2022-02-22更新
|
532次组卷
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3卷引用:福建省三明市永安第九中学2022-2023学年高二下学期返校考试数学试题
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4 . 以下说法中,正确的是( )
A.三棱锥![]() ![]() ![]() ![]() |
B.直线![]() ![]() ![]() ![]() ![]() |
C.G为![]() ![]() ![]() ![]() |
D.若点G为![]() ![]() ![]() |
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