1 . 指示函数是一个重要的数学函数,通常用来表示某个条件的成立情况.已知
为全集且元素个数有限,对于
的任意一个子集
,定义集合
的指示函数
若
,则( )
注:
表示
中所有元素
所对应的函数值
之和(其中
是
定义域的子集).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b52b4f24969673c863b5aff4fb6751ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b52b4f24969673c863b5aff4fb6751ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c37959331f824e0153871d62a13cb30e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c85325300b6ce106910cc9e758b56e6b.png)
注:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2059b60ca47a69612f16e1a3f63d8cf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
A.![]() |
B.![]() |
C.![]() |
D.![]() |
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2024-04-18更新
|
1189次组卷
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3卷引用:福建省安溪第八中学2024届高三下学期5月份质量检测数学试题
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2 . 聚点是实数集的重要拓扑概念,其定义是:
,
,若
,存在异于
的
,使得
,则称
为集合
的“聚点”,集合
的所有元素与E的聚点组成的集合称为
的“闭包”,下列说法中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f935b7601b228d3665631bf82bf03221.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c51159984b2cb00f30b3986315019623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/479a4db00b70dce0c5d88715851fa564.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38573dc7fb73024c610b7d123a449437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c254d67bba7f26489ff32cb12831095.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61588617d22abd00af4ca489bb3a8787.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61588617d22abd00af4ca489bb3a8787.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61588617d22abd00af4ca489bb3a8787.png)
A.整数集没有聚点 | B.区间![]() ![]() |
C.![]() | D.有理数集![]() ![]() |
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3 . 两个集合
和
之间若存在一一对应关系,则称
和
等势,记为
.例如:若
为正整数集,
为正偶数集,则
,因为可构造一一映射
.下列说法中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6c4704f64d12d5a12d7470eb02dc2c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6c4704f64d12d5a12d7470eb02dc2c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d63694528f708717928d3431ad0f0893.png)
A.两个有限集合等势的充分必要条件是这两个集合的元素个数相同 |
B.对三个无限集合![]() ![]() ![]() ![]() ![]() ![]() |
C.正整数集与正实数集等势 |
D.在空间直角坐标系中,若![]() ![]() ![]() ![]() ![]() |
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