解题方法
1 . 在长方体
中,已知
,
,
,点
为底面
内一点,若
和底面
所成角与二面角
的大小相等,点
在底面
的投影为点
,则三棱锥
体积的最小值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/305a88d4e0249bd16d48eda01331d2d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b59ab6bf6111dda4a3d428454768b77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ad3a1ea6790177130e16c2124984087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adebae2f9d7543915eb5a36427f9b6d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e07010ccdf2d83b7d3a6944034d3c95.png)
A.![]() | B.2 | C.![]() | D.![]() |
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解题方法
2 . 在平面直角坐标系
中,已知动点
到定点
的距离和它到定直线
的距离之比为
,记
的轨迹为曲线
.
(1)求
的方程;
(2)已知点
,不过
的直线
与
交于
,
两点,直线
,
,
的斜率依次成等比数列,求
到
距离的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90ce47fde921058026708a4321a0e213.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14e9efa96b6ec20a6ce18c7f458e4379.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/839c7616cd0d90265f4b2c9c021254fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)已知点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/383f12cb70ca55eba4ff012771dbfa9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84d454c82d9e52747563d47b68099249.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
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3 . 已知集合
,
,则满足条件
的集合
的个数为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a22f8d9188279429b395c30b2898ac1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baacdd9773a97d82cdb6a79ab7eae20d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd089af2b898c37371cee5ebbc07be7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.1 | B.2 | C.3 | D.4 |
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名校
4 . 设集合
为
的非空子集,随机变量X,Y分别表示取到子集
中的最大元素和最小元素的数值.
(1)若
的概率为
,求
;
(2)若
,求
且
的概率;
(3)求随机变量
的均值
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a6a4cff8424ced7841221e2d54d95d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6c4b25a0b76fba785d5769c08714b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41ab109ec88d6f3d24b2f01ca77e7038.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe08722cf9300fe188dbbb71989c06c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e32a2f594955e456f0fddad1e090bb04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8b3576b4d98a5b4ddc380ddaa0fa281.png)
(3)求随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec9f6ea6346066054b5c722763d6b026.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f8506fbcb1fae930e1503065b9327a.png)
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7日内更新
|
74次组卷
|
2卷引用:江苏省苏州大学2024届高三下学期高考考前数学指导卷
名校
解题方法
5 . 若集合
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c1b89fe395c978ab326dc0c5052db6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4b9b470218359a4a47be9244980489e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
6 . 已知函数
为定义在R上的减函数,函数
的图像关于点
对称,
满足不等式
,则当
时,
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2be344d1925b25e44f3f8b34d2c193ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53a948d2f7732d7f03e986c63712089b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b81c05456d97dc564fc5537816354fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd6ad6387d592102a743742620eee7fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b88584cf1df43e28d03592c7998b1653.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
名校
解题方法
7 . 红旗淀粉厂2024年之前只生产食品淀粉,下表为年投入资金
(万元)与年收益
(万元)的8组数据:
(1)用
模拟生产食品淀粉年收益
与年投入资金
的关系,求出回归方程;
(2)为响应国家“加快调整产业结构”的号召,该企业又自主研发出一种药用淀粉,预计其收益为投入的
.2024年该企业计划投入200万元用于生产两种淀粉,求年收益的最大值.(精确到0.1万元)
附:①回归直线
中斜率和截距的最小二乘估计公式分别为:
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6ae2ff5db33b7bd19c60ab2eb6e2b6a.png)
②
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![]() | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 |
![]() | 12.8 | 16.5 | 19 | 20.9 | 21.5 | 21.9 | 23 | 25.4 |
(1)用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/462bafa57981befbea871147abffeddf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)为响应国家“加快调整产业结构”的号召,该企业又自主研发出一种药用淀粉,预计其收益为投入的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b28555fa2f3a09261cb4e0305d390145.png)
附:①回归直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13557a1ebb8388eb2a9bb7ca9f0678b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5478b75ddd942ffcac4212ebe6642336.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6ae2ff5db33b7bd19c60ab2eb6e2b6a.png)
②
![]() | ![]() | ![]() | ![]() | ![]() |
161 | 29 | 20400 | 109 | 603 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5d46e43b31bf74c8adc17301f50940b.png)
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2024-03-22更新
|
1586次组卷
|
3卷引用:江苏省无锡市锡东高级中学2024届高三下学期4月月考数学试题
8 . 为了选拔创新型人才,某大学对高三年级学生的数学学科和物理学科进行了检测(检测分为初试和复试),共有4万名学生参加初试.组织者随机抽取了200名学生的初试成绩,绘制了频率分布直方图,如图所示.
的值及样本平均数的估计值;
(2)若所有学生的初试成绩
近似服从正态分布
,其中
为样本平均数的估计值,
.规定初试成绩不低于90分的学生才能参加复试,试估计能参加复试的人数;
(3)复试笔试试题包括两道数学题和一道物理题,已知小明进入了复试,且在复试笔试中答对每一道数学题的概率均为
,答对物理题的概率为
.若小明全部答对的概率为
,答对两道题的概率为
,求概率
的最小值.
附:若随机变量
服从正态分布
,则
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若所有学生的初试成绩
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdfc26b8bdcd1fd3781c4593217c725e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1100379a4385b9ce064847bc21760adc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30c2930011644c954b034dae8f4eea11.png)
(3)复试笔试试题包括两道数学题和一道物理题,已知小明进入了复试,且在复试笔试中答对每一道数学题的概率均为
![](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/6ca8b26c3ad6d892590290a2304126bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
附:若随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdfc26b8bdcd1fd3781c4593217c725e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/078df63aeb773d38d4bb320aedb87e68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc3c6437df0a45cd3a2d2d47009e30f0.png)
您最近一年使用:0次
2024-03-22更新
|
861次组卷
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3卷引用:2024届江苏省华罗庚中学高三下学期5月冲刺测试二数学试卷
名校
9 . 物理学家本·福特提出的定律:在b进制的大量随机数据中,以n开头的数出现的概率为
.应用此定律可以检测某些经济数据、选举数据是否存在造假或错误.若
,则k的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52e299852e6c767d1445835ddb194f3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8394427878f5327ee970a9e59c2c0a4e.png)
A.7 | B.8 | C.9 | D.10 |
您最近一年使用:0次
2024-03-13更新
|
1511次组卷
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6卷引用:2024届江苏省华罗庚中学高三下学期5月冲刺测试二数学试卷
10 . 将“用一条线段联结两个点”称为一次操作,把操作得到的线段称为“边”.若单位圆上
个颜色不相同且位置固定的点经过
次操作后,从任意一点出发,沿着边可以到达其他任意点,就称这n个点和k条边所构成的图形满足“条件
”,并将所有满足“条件
”的图形个数记为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33489e1a3bd3857a818bb0c6296da53a.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41b68080f1b8f75112406c0c5a8a0a93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33489e1a3bd3857a818bb0c6296da53a.png)
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2024-03-03更新
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1248次组卷
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7卷引用:江苏省泰州市2024届高三2月调研测试数学试题
江苏省泰州市2024届高三2月调研测试数学试题江苏省常州市金坛区2024届高三下学期调研测试(零模)数学试题江苏省南通市海安高级中学2023-2024学年高二下学期阶段检测(一)数学试题(已下线)压轴题08计数原理、二项式定理、概率统计压轴题6题型汇总广西壮族自治区贵港市2024届高三下学期模拟预测数学试题(已下线)6.2.3组合-6.2.4组合数——课时作业(提升版)单元测试B卷——第六章 计数原理