名校
解题方法
1 . 在
中,
,
,
,
分别在线段
和
上,
,
,直线
于
.现将三角形
沿着
对折,当平面
与平面
的二面角为
时,则线段
的长度为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43136f56e59f3f9e878d0c5d4ccbeecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ffc2817fa590affb5a760a25dc65308.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.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/98823cbc09ca52df1fbcc446eba3e44f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40c2b49d2e533b0e30f467e2660123e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1776d156423ea523de87fbca6c0b6019.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d78fc7fcb2762de28dcef8aa3aa0e49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
您最近一年使用:0次
2021-08-20更新
|
900次组卷
|
2卷引用:2021年全国高中数学联赛浙江赛区预赛试题
解题方法
2 . 设直角坐标平面上两个区域为
,
,记
与
的公共部分面积为
.当
时,则
的表达式为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da7b4d2af45f4af001a08d49d1161ee2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c6d5db1f2427972e79de8f6eee18082.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/2709ca478fb15ea08e8aa55328eae8e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23865ee52040331dee23621b4a15c244.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2709ca478fb15ea08e8aa55328eae8e6.png)
您最近一年使用:0次
3 . 对于正整数
,若
展开式经同类项合并,
合并后至少有2021项,则
的最小值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/332f0883a0a2b871baa31fd1942c7048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/965829b71df11e3d1160ce37fd8e3ed9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次