1 . 有机蔬菜是一类真正源于自然、富营养、高品质的环保型安全食品;绿色蔬菜是无机的.有机与无机主要标准是:有无使用化肥、农药、生长激素和转基因技术四个标准.有机蔬菜种植过程中不使用任何的人工合成的农药和化肥,但是绿色蔬菜在操作规程上是允许限量使用一些低毒,低残留的农药.种植有机蔬菜的土地一般来说都需要有三年或者三年以上的转换期,这就导致了种植有机蔬菜的时间成本高.某公司准备将M万元资金投入到该市蔬菜种植中,现有绿色蔬菜、有机蔬菜两个项目可供选择.若投资绿色蔬菜一年后可获得的利润
(万元)的概率分布列如下表所示:
且
的期望
;若投资有机蔬菜一年后可获得的利润
(万元)与种植成本有关,在生产的过程中,公司将根据种植成本情况决定是否在第二和第三季度进行产品的价格调整,两次调整相互独立且调整的概率分别为
(
)和
.若有机蔬菜产品价格一年内调整次数n(次)与
的关系如下表所示:
(1)求
的值;
(2)根据投资回报率的大小,现在公司需要决策:当
的在什么范围取值时,公司可以获得最大投资回报率.(投资回报率
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
95 | 126 | 187 | |
P | 0.5 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d93e7da0bbfce7ef7b753d5f3b9cf38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20c11f6c800b8e0410674a0c6d307d26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ae7fb954b47cb67fdde891c3b9d8295.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
0 | 1 | 2 | |
41.2 | 117.6 | 204.0 |
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
(2)根据投资回报率的大小,现在公司需要决策:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2a55b8f9885cdbdf39f6b8584841415.png)
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名校
2 . 某工厂生产某种元件,其质量按测试指标划分为:指标大于或等于82为合格品,小于82为次品,现抽取这种元件100件进行检测,检测结果统计如下表:
(1)现从这100件样品中随机抽取2件,若其中一件为合格品,求另一件也为合格品的概率;
(2)关于随机变量,俄国数学家切比雪夫提出切比雪夫不等式:
若随机变量X具有数学期望
,方差
,则对任意正数
,均有
成立.
(i)若
,证明:
;
(ii)利用该结论表示即使分布未知,随机变量的取值范围落在期望左右的一定范围内的概率是有界的.若该工厂声称本厂元件合格率为90%,那么根据所给样本数据,请结合“切比雪夫不等式”说明该工厂所提供的合格率是否可信?(注:当随机事件A发生的概率小于0.05时,可称事件A为小概率事件)
测试指标 | ![]() | ![]() | ![]() | ![]() | ![]() |
元件数(件) | 12 | 18 | 36 | 30 | 4 |
(2)关于随机变量,俄国数学家切比雪夫提出切比雪夫不等式:
若随机变量X具有数学期望
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4622b5c21e2262f58b6d3a49f7f26bf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2fabc25ba11deec2d0ae25504119002.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/711c92626a97e6b778b3aa86e663ee97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fe1c315b44af28c44bc7c468b4df733.png)
(i)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/422d29619b3d0c95ff8a3b1683b93d2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c25b1032d0e8b6ecc4baff0c521c6f27.png)
(ii)利用该结论表示即使分布未知,随机变量的取值范围落在期望左右的一定范围内的概率是有界的.若该工厂声称本厂元件合格率为90%,那么根据所给样本数据,请结合“切比雪夫不等式”说明该工厂所提供的合格率是否可信?(注:当随机事件A发生的概率小于0.05时,可称事件A为小概率事件)
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2024-03-21更新
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2661次组卷
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6卷引用:第七章 随机变量及其分布(提升卷)-2023-2024学年高二数学下学期重难点突破及混淆易错规避(人教A版2019)
(已下线)第七章 随机变量及其分布(提升卷)-2023-2024学年高二数学下学期重难点突破及混淆易错规避(人教A版2019)云南省昆明市第三中学2023-2024学年高二下学期5月期中考试数学试题浙江省金丽衢十二校2024届高三下学期第二次联考数学试题辽宁省2024届高三下学期3+2+1模式新高考适应性统一考试数学试卷江苏省姜堰中学2024届高三下学期阶段性测试(2.5模)数学试题(已下线)浙江省金丽衢十二校2024届高三下学期第二次联考数学试题变式题16-19
解题方法
3 . 如图已知抛物线C的方程为
,焦点为F,过抛物线内一点A作抛物线准线的垂线,垂足为
,与抛物线交于点P,已知
,
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/95123bb1-911d-4d72-8335-f305e8e71eb2.png?resizew=166)
(1)求p的值;
(2)斜率为k的直线过点
,且与曲线C交于不同的两点M,N,已知k的取值范围为
,探究:是否存在
,使得
,若存在,求出
的范围,若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7089148c36cb3c39af71de653756396a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c314398e26ffc7164b82946eeb4273.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd21a4e45dc1beb069d7e78f84a51544.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90675b0443eaa6607d217e6a32a690b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b885ab7c607be0dbd27c1e57941e81f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/95123bb1-911d-4d72-8335-f305e8e71eb2.png?resizew=166)
(1)求p的值;
(2)斜率为k的直线过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/137c4624509cdea01ec665854cfb03d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afa482d7bcaa385bfc3548b42a4bfb60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0df31126849d010525cbeee019bae5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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2023-11-26更新
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501次组卷
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2卷引用:安徽省淮北市树人高级中学2023-2024学年高二上学期期中数学试题
4 . 设
为正实数,若各项均为正数的数列
满足:
,都有
.则称数列
为
数列.
(1)判断以下两个数列是否为
数列:
数列
:3,5,8,13,21;
数列
:
,
,5,10.
(2)若数列
满足
且
,是否存在正实数
,使得数列
是
数列?若存在,求
的取值范围;若不存在,说明理由.
(3)若各项均为整数的数列
是
数列,且
的前
项和
为150,求
的最小值及取得最小值时
的所有可能取值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bde2576b383ae3c851529435805b3adc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/428dccc2ca7913400fd6644fb78de601.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ee7ed704a954d0414be6c3148bd566d.png)
(1)判断以下两个数列是否为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bea0dd7e474bcd04db2544427ba0488.png)
数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5faff5d08e2976e15f0cec988ced37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70f5389990c3a0c5373f3bd9fb2454c9.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d765033fa3e470b4b4bae90a28514587.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/585e3a2fda3f7f3b5b484c9113a3c59f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ee7ed704a954d0414be6c3148bd566d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(3)若各项均为整数的数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d8f894492a8126f5f133dec4cd68833.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1071ac8657ef1c4e1ea7e0530196298d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc94ddf603ec2e0af31695f6654b2d99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b47bfab3010d4aa7e17cd1b54e26c157.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681ae1522a36768618f7ddaf74abbb7e.png)
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2023-01-05更新
|
601次组卷
|
3卷引用:河北省邯郸市魏县2022-2023学年高二上学期期末考试数学试题
5 . 已知圆C:
.
(1)当
,
,
时,过点
且斜率为k的直线l与圆C有两个不同的交点,求k的取范围;
(2)当圆C以坐标原点O为圆心,且与直线
相切时,圆与x轴交于A,B两点,圆内的动点P使
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58d7c223faadd624d524399fc0f7f39e.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e258ab9e600435b37465092243d99f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcdb7a488910743dc5c63afb394b87e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7551011cfb75b26f35b07d6617c6a18b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b25e326fdf9e5456f48e8a99a069f379.png)
(2)当圆C以坐标原点O为圆心,且与直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bb2c3c88ffd31fe98cb36b03566cca8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc495b7c04ff1d3c2bd7098bf96c5649.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59880e470359d8e9faf6ae5ce155cf2a.png)
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解题方法
6 . 《绿色通道》作业88面第12题:已知双曲线
左右两个焦点分别为
,过
的直线交双曲线的右支于点
,且满足:
,
的周长等于焦距的3倍,若
,则双曲线离心率的取值范围是______.
我校高二某班的小楚同学在处理这个题目时提出了自己的见解,他认为这个曲线的离心率在已知比例和周长的条件下应该是个确定的值而不是某个范围,所以条件
可能是个多余的“伪条件”.你是否认同小楚同学的观点?若认同,请你求出此曲线的离心率,若不认同,请你说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a01e0c43c8c52d04824420717eb52969.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d2a97987f71835f519b462f5b8f5957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3a7681c38f74e21181bb9de077b0c0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3c07ebcbfacda073208d483c58e8a84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/291d1caba33704c0a5ddaf328e0f6037.png)
我校高二某班的小楚同学在处理这个题目时提出了自己的见解,他认为这个曲线的离心率在已知比例和周长的条件下应该是个确定的值而不是某个范围,所以条件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/291d1caba33704c0a5ddaf328e0f6037.png)
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7 . 定义一种新的运算“
”:
,都有
.
(1)对于任意实数a,b,c,试判断
与
的大小关系;
(2)若关于x的不等式
的解集中的整数恰有3个,求实数a的取值范围;
(3)已知函数
,
,若对任意的
,总存在
,使得
,求实数m的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c3c2f679d53b91088ba6eb14c16cbc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2671f593186fa00f17ad26eba7b8f3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a8c23336002eb5d7c478479fcda799f.png)
(1)对于任意实数a,b,c,试判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fda9c56c7993236c0ebdfe08d110ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b98e8a20e1e3d328265269df6b2927ad.png)
(2)若关于x的不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b80fef6a2dd7e822d83ae45ea79a5357.png)
(3)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06fc1f7733bebb86885b6e6fd0534e1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d8b60555f0d82c386c5b935c23ff952.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12965bbc260bdbb0df0a110e59fb8d78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93bf66ef253242900ca1702121238b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52dc0bb1b1d25a0e86babc0edc627e44.png)
您最近一年使用:0次
2023-07-11更新
|
527次组卷
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3卷引用:山东省青岛市莱西市2022-2023学年高二下学期期末数学试题
名校
8 . 给出函数
,
(1)若
,求不等式
的解集;
(2)若
,且
,求
的取值范围;
(3)若
,非零实数
,
满足
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f18cf2aa76c59569a668ee8fb5ae420.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b4d795709b0abcf47bceec2250f2f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f62acc97e485075f489e1d5e96e09958.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/867f0794e209c2aa6dc1ded523427ec7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b4d795709b0abcf47bceec2250f2f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea3c5462af41f417a830b88fbad13bbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01e1d71a91451f7086d9237c0fea607e.png)
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名校
9 . 记
(
),
(
).
(1)若
的解集为
,求
和
的值;
(2)若方程
和
都没有实数根,求证:方程
和
至少有一个没有实数根;
(3)若
,对任意的
,都存在
使得关于
的不等式
有解,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2755fcabc5ee31d2fc498fe2c49b03f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e0137d9ccd136186c2fe74a11e42376.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2fade3a0936bce1f314c8e264aa6d24.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7569cd7e9b31ad838230133b9bc8314.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e44284cb19805a584880a686ac3df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5f5e5688b5c7e514ee72597690a7676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(2)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab07e032a53680089686bbbcd27c4414.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c3e204cd5978cb40f691e040438e3c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/804c9cadb1f88ae4d408c94294ba5902.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e9c644eb85873694490f987e9525805.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c579f7b3a3c7b6b5c70cf826ef91da37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e0137d9ccd136186c2fe74a11e42376.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2bf33032e4f44ff4e9473e069dd8be5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/142ddc55e14c91623d09684307af2d48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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