名校
解题方法
1 . 故宫角楼的屋顶是我国十字脊顶的典型代表,如图1,它是由两个完全相同的直三棱柱垂直交叉构成,将其抽象成几何体如图2所示.已知三楼柱
和
是两个完全相同的直三棱柱,侧棱
与
互相垂直平分,
交于点I,
,
,则点
到平面
的距离是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5399fca789fea184a162bfb6d95afd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9f523fc81603a5c4cdff956a5c3298b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8856a6bbd1648fef7aaa384366e9016f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8df32f10590eccf0d07989db09ad7d48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c507610f462120218e2cd1894c957eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd4b93d7abcfc4c3df48f03aa969c17f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
今日更新
|
480次组卷
|
3卷引用:【北京专用】高二下学期期末模拟测试A卷
2 . 已知数列
具有性质
:
, 都
,使得
.
(1)分别判断以下两个数列是否满足性质
,并说明理由;
(ⅰ)有穷数列
:
;
(ⅱ)无穷数列
:
;
(2)若有穷数列
满足性质
,且各项互不相等,求项数
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1513eaa448529cd58c109c7cba21f17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef87407d7df837d44f2780285383955b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab406d94b4907ab8a20ae3214628b045.png)
(1)分别判断以下两个数列是否满足性质
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(ⅰ)有穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/305fba5be99a52f61dd8f868ec3c9f17.png)
(ⅱ)无穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b52595e3f2338ee60f0f024162d1da2.png)
(2)若有穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
3 . 函数
的最小值及取得最小值时
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dd0d2ddf02f569989540cdefc181e5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
A.当![]() ![]() | B.当![]() ![]() |
C.当![]() ![]() | D.当![]() ![]() |
您最近一年使用:0次
4 . 在机器学习中,精确率
、召回率
、卡帕系数
是衡量算法性能的重要指标.科研机构为了测试某型号扫雷机器人的检测效果,将模拟战场分为100个位点,并在部分位点部署地雷.扫雷机器人依次对每个位点进行检测,
表示事件“选到的位点实际有雷”,
表示事件“选到的位点检测到有雷”,定义:精确率
,召回率
,卡帕系数
,其中
.
(1)若某次测试的结果如下表所示,求该扫雷机器人的精确率
和召回率
.
(2)对任意一次测试,证明:
.
(3)若
,则认为机器人的检测效果良好;若
,则认为检测效果一般;若
,则认为检测效果差.根据卡帕系数
评价(1)中机器人的检测效果.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.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/035744497a9eb070b633d78e5a2973ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c150fe2837b2d6a191e77fcc4fd984d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/016078f7e8096746515b68f3d88e6edf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7999bf73a3e99b33a7dc9e27605f13ea.png)
(1)若某次测试的结果如下表所示,求该扫雷机器人的精确率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
实际有雷 | 实际无雷 | 总计 | |
检测到有雷 | 40 | 24 | 64 |
检测到无雷 | 10 | 26 | 36 |
总计 | 50 | 50 | 100 |
(2)对任意一次测试,证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01e8b6a9cfa7a1f79de242e13701a8d2.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/326127fdb2c7118ad2c942704c35bf89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a914996508a498faac0d74e21536cb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb4f8b2dcaf2be0c42f852400d758acd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
名校
5 . 已知总体分为2层,通过分层随机抽样,各层抽取的样本量、样本平均数和样本方差分别为:
,
,
;
,
,
.记总样本的平均数为
,样本方差为
.
(1)试证明:
;
(2)在对某高中1500名高三年级学生的身高的调查中,采用按学生性别比例分配的分层随机抽样抽取100人,已知这1500名高三年级学生中男生有900人,且抽取的样本中男生的平均数和方差分别为170cm和12,女生的平均数和方差分别为160cm和38.试用(1)证明的公式估计高三年级全体学生身高的方差.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27c44826e58f11a58d3a6c233fc5df2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfbe7f95b5d89f9409ec24536da9e826.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfbc29b47b83fdc5368770b7b1acb439.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/215b1424b299b737554386b090af8316.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb525270c748eddaaecc4a549cca250e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab1295cbd36fdc55a55b549aa2dd5887.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02931526ba46098639424f341794bd45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f43c79d612c93a6d160335e86e177.png)
(1)试证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06119159922742550d148c6fb8ddfb02.png)
(2)在对某高中1500名高三年级学生的身高的调查中,采用按学生性别比例分配的分层随机抽样抽取100人,已知这1500名高三年级学生中男生有900人,且抽取的样本中男生的平均数和方差分别为170cm和12,女生的平均数和方差分别为160cm和38.试用(1)证明的公式估计高三年级全体学生身高的方差.
您最近一年使用:0次
6 . 设集合
,点P的坐标为
,满足“对任意
,都有
”的点P构成的图形为
,满足“存在
,使得
”的点P构成的图形为
.对于下述两个结论:①
为正方形以及该正方形内部区域;②
的面积大于32.以下说法正确的为( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03cd04b82dda9c0d2dd0957ffc407d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82a79a33a83a7ba57a34b5093d1d1d02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9712a0071f6d0d78d17ce18f6084cad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3693b84b83679c30b1035750d9b4f2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deebd2c36a5e644a566f1980091359bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9712a0071f6d0d78d17ce18f6084cad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3693b84b83679c30b1035750d9b4f2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89e32039addb008103a2a8344225214a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deebd2c36a5e644a566f1980091359bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89e32039addb008103a2a8344225214a.png)
A.①、②都正确 | B.①正确,②不正确 |
C.①不正确,②正确 | D.①、②都不正确 |
您最近一年使用:0次
7 . 已知数列
,从
中选取第
项、第
项、…、第
项
构成数列
,
称为
的
项子列.记数列
的所有项的和为
.当
时,若
满足:对任意
,
,则称
具有性质
.规定:
的任意一项都是
的
项子列,且具有性质
.
(1)当
时,比较
的具有性质
的子列个数与不具有性质
的子列个数的大小,并说明理由;
(2)已知数列
.
(ⅰ)给定正整数
,对
的
项子列
,求所有
的算术平均值;
(ⅱ)若
有
个不同的具有性质
的子列
,满足:
,
与
都有公共项,且公共项构成
的具有性质
的子列,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/281440c5e428da28c0a40fecbb87a83a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a745b1425e102f3b0b21ee9f0ad3b00c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4104fe7904b991cdb2f081aab13883bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c3b8d44073da406348fc6c9dd4ea068.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a92f44c615d77249c2714cfb388fec84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c91e6d0611914758f7f0fe01b592f1b.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/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e965bb0f1d58c6ae573635f7bb4176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c972cbd63decec197aec1bdc306de67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55507a1da1dfff5cc76e47d62830fa9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a9889f58c052eba0ff037c0ca7b4935.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c663bea75eddb0c7f1885079c88b956e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fac3649308b528fd56545ba102dc42d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(2)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdea316b1aa1563c8bf3c2b81c09ce69.png)
(ⅰ)给定正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f72bc968a860f8ac4d77d51ce93840d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e965bb0f1d58c6ae573635f7bb4176.png)
(ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7184704e17e83f3ac39e5fee6b3aa11e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b627bbe576616595035f10bcc0aa8cdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdc5c895153932c3e827a464664cef90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51a2d8cb9e08ce79015879ea2744e351.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
2024高三下·全国·专题练习
8 . 如图,已知
是
的垂心,且
,则
等于( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6df40eff7ee933766046dd1aa53ab2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8196337d759c33632aa0dc3d4ad50716.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
9 . 2023年6月22日,由中国帮助印尼修建的雅万高铁测试成功,高铁实现时速
自动驾驶,不仅速度比普通列车快,而且车内噪声更小.如果用声强
(单位:
)表示声音在传播途径中每平方米上的声能流密度,声强级
(单位:
)与声强
的函数关系式为
,其中
为基准声强级,
为常数,当声强
时,声强级
.下表为不同列车声源在距离
处的声强级:
设在离内燃列车、电力列车、高速列车
处测得的实际声强分别为
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd054da0ad34c8ba01fe54179ba0a7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e105760638b22b26ff8bec4354255e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db72d10094c3d5cf2cb4eaa4809a1f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca586d4c35ce52dec4b545cf13ee0721.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e105760638b22b26ff8bec4354255e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7980ec6e0e432b23fbe3f4562848913.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/164932c352061abf01e7e3513b08229d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f0a1908e167c64684b0a50aee5ec64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e3a88ef910aa647ac022c3880262f78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c08094f72d5bd69246c453dd28e33d1.png)
声源 | 与声源的距离(单位:![]() | 声强级范围 |
内燃列车 | 20 | ![]() |
电力列车 | 20 | ![]() |
高速列车 | 20 | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c08094f72d5bd69246c453dd28e33d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/146e570dfac0a06f1547a444808701d9.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2024-04-08更新
|
229次组卷
|
6卷引用:【北京专用】高二下学期期末模拟测试B卷
(已下线)【北京专用】高二下学期期末模拟测试B卷四川省百师联盟2024届高三冲刺卷(二)全国卷理科数学试题(已下线)情境4 重视学科交叉陕西省安康市高新中学、安康中学高新分校2024届高三下学期4月联考模拟预测(理科)数学试题(已下线)第08讲 函数模型及其应用(五大题型)(练习)2024届陕西省安康市高新中学、安康中学高新分校4月联考模拟预测文数试题
名校
10 . 当药品
注射到人体内,它在血液中的残余量会以每小时25%的速度减少.
(1)按照医嘱,护士给患者甲注射了
药品
两小时后,患者甲血液中药品
的残存量为
,求
的值;
(2)另一种药物
注射到人体内,它在血液中的残余量会以每小时10%的速度减少.如果同时给两位患者分别注射
药品
和
药品
,请你计算注射后几个小时两位患者体内两种药品的残余量恰好相等.(第(2)问计算结果保留2位小数)
参考值:
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)按照医嘱,护士给患者甲注射了
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7428057b4757de6d1d510712f01465e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55354a714cdf174cf4ebd43a2f041bbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)另一种药物
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc2baea0d7b4cae52246ff279a41e460.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/618c8bb0c6e025b11eeb7da738183d1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
参考值:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a49dc2827f437b3a1e7cbc25c680093c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51988fef1f0ae3f710f36865834790e5.png)
您最近一年使用:0次