1 . 命题
:在二项式
的展开式中,各二项式系数之和为
.命题
:随机变量
满足
,则
,下列命题是假命题的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9216a0f9d6e65ea4937ab7bf102c5db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f31971306914638e5ceb1bbe437535d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a0d6d3c70c9190296cc8e9a08e54312.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fced3a87cab2aad137ce376e18fbf6c5.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
2022-09-06更新
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299次组卷
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2卷引用:四川省泸州市2021-2022学年高二下学期期末数学(理)试题
名校
2 . 在贯彻中共中央国务院关于精准扶贫政策的过程中,某单位定点帮扶甲、乙两个村各50户贫困户.为了 做到精准帮扶,工作组对这100户村民的年收入情况、劳动能力情况、子女受教育情况、危旧房情况、 患病情况等进行调查,并把调查结果转化为各户的贫困指标
和
,制成下图,其中“
”表示甲村贫困户,“
”表示乙村贫困户.若
,则认定该户为“绝对贫困户”,若
,则认定该户为“相对贫困户”,若
,则认定该户为“低收入户”;若
,则认定该户为“今年能脱贫户”,否则为“今年不 能脱贫户”.
![](https://img.xkw.com/dksih/QBM/2018/5/31/1957222732111872/2025210947936256/STEM/99307c2d548d458b886a577bf68615a2.png?resizew=390)
(1)从甲村50户中随机选出一户,求该户为“今年不能脱贫的绝对贫困户”的概率;
(2)若从所有“今年不能脱贫的非绝对贫困户”中选3户,用
表示所选3户中乙村的户数,求
的分布 列和数学期望
;
(3)试比较这100户中,甲、乙两村指标
的方差的大小(只需写出结论).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc7d51315fcca519cb58bacd0040d7de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d4cd9a7068de096606d1ab991f5e6da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fab7ddc4797c4b8432797829d9721bd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4820668125cc915107cf3ceb6ae1f0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3ad7c138bcd59045fcb3eedcc90f920.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe4a66fc470db7dd5cd328adb1b4889c.png)
![](https://img.xkw.com/dksih/QBM/2018/5/31/1957222732111872/2025210947936256/STEM/99307c2d548d458b886a577bf68615a2.png?resizew=390)
(1)从甲村50户中随机选出一户,求该户为“今年不能脱贫的绝对贫困户”的概率;
(2)若从所有“今年不能脱贫的非绝对贫困户”中选3户,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefcbf930fe7ffbfeaba7f13cdba3884.png)
(3)试比较这100户中,甲、乙两村指标
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
您最近一年使用:0次
2018-03-30更新
|
1027次组卷
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6卷引用:四川省泸州市泸县第五中学2020届高三下学期第二次高考适应性考试数学(理)试题