名校
1 . 设集合
,现对
的任意一非空子集
,令
表示X中最大数与最小数之和,则所有这样的
的算术平均数为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d1fe401454b959800d64bfece4cf231.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6363a3aacd1569dc144cc27ed85ba6f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6363a3aacd1569dc144cc27ed85ba6f6.png)
您最近一年使用:0次
2 . 给定整数
,记
为集合
的满足如下两个条件的子集
的元素个数的最小值:ⅰ.
,
;ⅱ.子集
中的元素(除1外)均为
中的另两个(可以相同)元素的和.
(1)求
的值;
(2)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8715a3f984d2627afd7c40c61347b7cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38fcec7af3520884b173b29bda6c657a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab6a1d0b6255d2fe84bfad2e4ad232d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35a2410ce34b36954ed4923e600d42f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/006862363f0414fa9eaa25411bfbc1f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9347bb4ffedcbea2f4c16d047a138d75.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecd61ca77c54e98408bd4bfe5898671b.png)
您最近一年使用:0次
2018-12-14更新
|
216次组卷
|
3卷引用:2012年新知杯上海市高中数学竞赛试题
2014高三·湖北·竞赛
名校
3 . 若
,且
,
,则
称为集合
的孤立元素那么,集合
的无孤立元素的四元子集有______ 个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cc020b0997a2f37b214718112b79d8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c50c209f8710e0ce1e0c64042aa4d34a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2368f7373e7ae3bd33f58fcfc84c8460.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd92f9c7b1ec78816000707caf2adb7b.png)
您最近一年使用:0次
2018-12-05更新
|
167次组卷
|
3卷引用:2014年全国高中数学联赛湖北赛区预赛试题