1 . 在信道内传输0,1信号,信号的传输相互独立.发送0时,收到1的概率为
,收到0的概率为
;发送1时,收到0的概率为
,收到1的概率为
.
(1)重复发送信号1三次,计算收到1的次数
的分布列及期望;
(2)依次发送1,1,0,判断以下两个事件:①事件
:至少收到一个正确信号;②事件
:至少收到两个0,是否互相独立,并给出证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
(1)重复发送信号1三次,计算收到1的次数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)依次发送1,1,0,判断以下两个事件:①事件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
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2 . 某公司为了解年研发资金
(单位:亿元)对年产值
(单位:亿元)的影响,对公司近8年的年研发资金
和年产值
(
,
)的数据对比分析中,选用了两个回归模型,并利用最小二乘法求得相应的
关于
的经验回归方程:
①
;②
.
(1)求
的值;
(2)已知①中的残差平方和
,②中的残差平方和
,请根据决定系数选择拟合效果更好的经验回归方程,并利用该经验回归方程预测年研发资金为20亿元时的年产值.
参考数据:
,
,
,
.
参考公式;刻画回归模型拟合效果的决定系数
.
![](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/97ea8f47d8d8d9e1832d52b1c7425450.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4de122ae929b1acaff321dec137622ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e2928f2bf2a086d6301b5352f7ef1aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ac190405449cba34174ed6705aa6ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/718cfed01c71b2fc805d8d7100b91dc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c676941ea413d829060d29befd59d554.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5292c735338a9c57f86b2b2442261bef.png)
(2)已知①中的残差平方和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44f23c3d6eb2728ae5c1171eac969b09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4515125add629aa249ac0e14f01b257.png)
参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/194bfb08c0f47c01de5bfe5660d423a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/788b03267c223ba0538552371aa1a31b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/748e20fa23b995da6aa1c5936bf38117.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f4cbe45f8c50795b37c9925414ea816.png)
参考公式;刻画回归模型拟合效果的决定系数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72c8cd473a8b5a8da1f04b5041e609b0.png)
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解题方法
3 . 有
个编号分别为1,2,…,
的盒子,第1个盒子中有3个白球1个黑球,其余盒子中均为1个白球1个黑球,现从第1个盒子中任取一球放入第2个盒子,再从第2个盒子中任取一球放入第3个盒子,以此类推,从第
个盒子中取到白球的概率是_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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4 . 学校将先后组织篮球和足球比赛,需要体育协会的同学来当裁判员.已知8名体育协会的同学中,有6人能胜任足球裁判,4人能胜任篮球裁判,现需要篮球,足球裁判各3人,则一共有_________ 种安排方法.
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5 . 伯努利双纽线最早于1694年被瑞士数学家雅各布·伯努利用来描述他所发现的曲线.在平面直角坐标系
中,把到定点
,
距离之积等于
的点的轨迹称为双纽线,已知点
是
的双纽线
上一点,下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcb162568cb923c31c7209c8a22e4674.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cca4d2dd6a806193dfd4d66991a48a82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be45dd63a0db0b7ab458f30ee6a67881.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aee82283f06cedef32eb15b87964f5d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.若直线![]() ![]() ![]() ![]() ![]() ![]() ![]() |
B.双纽线![]() ![]() |
C.![]() ![]() |
D.![]() ![]() |
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6 . 已知
,
,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33f306d2b261f4c39a9fc0858d96e647.png)
A.若![]() ![]() | B.若![]() ![]() |
C.若![]() ![]() | D.![]() ![]() |
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解题方法
7 . 某儿童医院用甲、乙两种疗法治疗小儿消化不良.采用有放回简单随机抽样的方法抽取足够样本后对治疗情况进行检查,得到两种疗法治疗数据的列联表后,经计算得到
,则可以认为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0659a40bee5dae80a08f76277ac1b8f.png)
A.根据小概率值![]() ![]() ![]() |
B.根据小概率值![]() ![]() ![]() |
C.根据小概率值![]() ![]() ![]() |
D.根据小概率值![]() ![]() ![]() |
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8 . 设
,
,
则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c5748fb8d839ae50cdb0faf6adaf41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87bd9f5db8b97abf9bdd15b8efb6c64d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6db65c5fa71af60d067f32e1a70774cd.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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9 . 设数列
的前
项的和为
,若对任意的
,都有
,则称数列
为“超级数列”.已知
是首项为正数、公比为
的等比数列,若
为“超级数列”,则公比
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e5f09b3177347a65b656568909ac14e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b2c86af4416911af577d14afa08740d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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10 . 某省高考改革试点方案规定:2023年高考总成绩由语文、数学、外语三门统考科目和思想政治、历史、地理、物理、化学、生物六门选考科目组成,将每门选考科目的考生原始成绩从高到低划分为
,
,
,
,
,
,
,
共8个等级,参照正态分布原则,确定各等级人数所占比例分别为
,
,
,
,
,
,
,
,选考科目成绩计入考生总成绩时,将
至
等级内的考生原始成绩,依照等比例转换法则,分别转换到
,
,
,
,
,
,
,
八个分数区间,得到考生的等级成绩,如果该省某次高考模拟考试物理科目的原始成绩
,那么
等级的原始分最低大约为( )
参考数据:对任何一个正态分布
来说,通过
转化为标准正态分布
,从而查标准正态分布表得到
.可供查阅的(部分)标准正态分布表:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8a5d766aad11b1c32dabf6e3eada26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2882b9baf240d68e92d67dabb12cd332.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e194680eeb097a6b5f3b834d3b97688.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8caa734b124b6278bd4a5e522484428.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc7b40bdfb3886053cbcc7076ec0d5b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e41a9e9bb3c6ddd2b1ab7d11f3113b7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce364f3ee5161f09e39687f3e8b53b9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce364f3ee5161f09e39687f3e8b53b9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e41a9e9bb3c6ddd2b1ab7d11f3113b7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc7b40bdfb3886053cbcc7076ec0d5b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8caa734b124b6278bd4a5e522484428.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c601a1f38803fe4b55f984e552a91497.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/175e50796ba40cfa2e59114fa0336369.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18e57ff4b2a51a53205079a0f6b5fb35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc623c4c3659db5ac097e75d1b9b2d4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5123492edf8de510cfb2a422bf374e2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31c68ed009b633967fe43494ee801d59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25be4d66eb9c5185081443686f118545.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2470c35cfe8265ec4cdcc71befbd2664.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80914c4d48c673f39f8b2a518005dda9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8a5d766aad11b1c32dabf6e3eada26.png)
参考数据:对任何一个正态分布
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1290917c2c835b61384480b335cc1d13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606a7a4ce17d92cd3bca4bc9efb9a8fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/333e52e2291c6daaf14675b5185bd4b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc4b27bf6783be534b99d59d3157c2cf.png)
1.1 | 1.2 | 1.3 | 1.4 | 1.5 | 1.6 | 1.7 | 1.8 | 1.9 | |
0.8643 | 0.8849 | 0.9032 | 0.9192 | 0.9332 | 0.9452 | 0.9554 | 0.9641 | 0.9713 | |
2.0 | 2.1 | 2.2 | 2.3 | 2.4 | 2.5 | 2.6 | 2.7 | 2.8 | |
0.9772 | 0.9821 | 0.9861 | 0.9893 | 0.9918 | 0.9938 | 0.9953 | 0.9965 | 0.9974 |
A.57 | B.64 | C.71 | D.77 |
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