解题方法
1 . 某数学兴趣小组模拟“刮刮乐”彩票游戏,每张彩票的刮奖区印有从10个数字1,2,3,…,10中随机抽取的3个不同数字,刮开涂层即可兑奖,中奖规则为:每张奖卷只能中奖一次(按照最高奖励算)若3个数的积为3的倍数且不为5的倍数时,中三等奖;若3个数的积为5的倍数且不为3的倍数时,中二等奖;若3个数的积既为3的倍数,又为4的倍数,又为7的倍数时,中一等奖;其他情况不中奖.
(1)随机抽取一张彩票,求这张彩票中奖的概率;
(2)假设每张彩票售价为
元,且获得三、二、一等奖的奖金分别为5元,10元,50元,从出售该彩票可获利的角度考虑,求
的最小值.
(1)随机抽取一张彩票,求这张彩票中奖的概率;
(2)假设每张彩票售价为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/763da45bcb3807b491cf2f869471bd76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
2024-02-29更新
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1843次组卷
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5卷引用:内蒙古赤峰第四中桥北学分校2024届高三下学期开学摸底联考数学(理)试题
2 . 有一张矩形纸片
,按下面步骤进行折叠:
第一步:如图①,将矩形纸片
折叠,使点
,
重合,点
落在点
处,得折痕
;
第二步:如图②,将五边形
折叠,使
,
重合,得折痕
.再打开;
第三步:如图③,进一步折叠,使
,
均落在
上,点
,
落在点
处,点
,
落在点
处,得折痕
,
.
这样,就可以折出一个五边形
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/f542cf2b-0c93-4fa8-ac31-578892903940.png?resizew=141)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/669fd515-afbb-46a9-8023-86dc67d158c2.png?resizew=141)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/6c2b59a9-a749-4b81-9264-bd4b80f19283.png?resizew=141)
(1)适当添加辅助线,请写出图①中三组全等三角形______,______,______;(写出不同的三组即可)
(2)若这样折出的五边形
(如图③)恰好是一个正五边形,当
,
,
①请写出一个
与
的关系式,并加以证明;
②设正五边形的边长
,请求出边长
(用
或
表示
).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
第一步:如图①,将矩形纸片
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c8a9c4957431681ddfc77895a88508.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
第二步:如图②,将五边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8149f05bbaf25926ad9ac243a04b482.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae72f1da4f5d540dc1e6f42ea08f952e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
第三步:如图③,进一步折叠,使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae72f1da4f5d540dc1e6f42ea08f952e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c8a9c4957431681ddfc77895a88508.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c314398e26ffc7164b82946eeb4273.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b1a5427d8ff23df0f3ec194756c84c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f6927cc2a930203ac34366383e76ef.png)
这样,就可以折出一个五边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db24888830edd7df393bf95fde1281e8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/f542cf2b-0c93-4fa8-ac31-578892903940.png?resizew=141)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/669fd515-afbb-46a9-8023-86dc67d158c2.png?resizew=141)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/6c2b59a9-a749-4b81-9264-bd4b80f19283.png?resizew=141)
(1)适当添加辅助线,请写出图①中三组全等三角形______,______,______;(写出不同的三组即可)
(2)若这样折出的五边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db24888830edd7df393bf95fde1281e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d42e97eee705d164e6ac6de9ecd6d1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c52b857c7ca55dfa6da108df1d3cee2.png)
①请写出一个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
②设正五边形的边长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c21350a49d9229ef239253f7c3d366ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](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/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
名校
解题方法
3 . 复数是由意大利米兰学者卡当在十六世纪首次引入,经过达朗贝尔、棣莫弗、欧拉、高斯等人的工作,此概念逐渐为数学家所接受.形如
的数称为复数,其中
称为实部,
称为虚部,i称为虚数单位,
.当
时,
为实数;当
且时,
为纯虚数.其中
,叫做复数
的模.设
,
,
,
,
,
,
如图,点
,复数
可用点
表示,这个建立了直角坐标系来表示复数的平面叫做复平面,
轴叫做实轴,
轴叫做虚轴.显然,实轴上的点都表示实数;除了原点外,虚轴上的点都表示纯虚数.按照这种表示方法,每一个复数,有复平面内唯一的一个点和它对应,反过来,复平面内的每一个点,有唯一的一个复数和它对应.一般地,任何一个复数
都可以表示成
的形式,即
,其中
为复数
的模,
叫做复数
的辐角,我们规定
范围内的辐角
的值为辐角的主值,记作
.
叫做复数
的三角形式.
,
,求
、
的三角形式;
(2)设复数
,
,其中
,求
;
(3)在
中,已知
、
、
为三个内角
的对应边.借助平面直角坐标系及阅读材料中所给复数相关内容,证明:
①
;
②
,
,
.
注意:使用复数以外的方法证明不给分.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c0c72c17b74f9a5a175ec2b9d77e7.png)
![](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/c789a7cd7ac2b8b96dc879c6c8161ee4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/143b917df0520097be222accbddf9394.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03b011f69dfc5262a3d82f64676739b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22fe68ea0bf368925909606949da47f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a0bf9b2a7378e73e9fd06c693bfda07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/368f9e12546277731776041c73dbe58c.png)
![](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/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80e80e5baee553150c67a91f1017a7be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb6958203312cbda12fd2683a819dd9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e472aea001d179c284e3687a9aacf384.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b40b6895776e0807c2baecbc8f33a8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e472aea001d179c284e3687a9aacf384.png)
![](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/4b40b6895776e0807c2baecbc8f33a8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec45476379fb51aa1ef0a93f849f48be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e283f3168c0b5e8f68dda92c43651e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eec3e684af41f9ed4db5b931b9ccfb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f56cfb41ee7cb758fee138ab09e0d13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec45476379fb51aa1ef0a93f849f48be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b40b6895776e0807c2baecbc8f33a8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3665b2dac544bfb2a0c175f95a480e1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91b3a15906b84b98a3ac563e7e2ec9c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fe615164ed2995bdeea0f5b0ba94231.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec04f844e8fd9d9b1ef835e23eaa54e2.png)
(2)设复数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd87d6e1987cf95d102de1045d3722a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/398d8980d3ec9fbf536a1efa6312a19a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0492634f27279b6470798af0185be67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c723970ac738976e0130e1438b67058.png)
(3)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](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/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1501d4035822b34fcc2378f1e316f159.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e63471f592531e46277365ed319e2acc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b923694c299d953e02cb79dfcef9f56a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5ce2f54d69a5987c1de19da53342811.png)
注意:使用复数以外的方法证明不给分.
您最近一年使用:0次
2024-03-12更新
|
579次组卷
|
4卷引用:黑龙江省哈尔滨师范大学附属中学2023-2024学年高一下学期开学考试数学试卷
黑龙江省哈尔滨师范大学附属中学2023-2024学年高一下学期开学考试数学试卷重庆市缙云教育联盟2023-2024学年高一下学期3月月度质量检测数学试题(已下线)模块五 专题六 全真拔高模拟2(已下线)第七章:复数(新题型)-同步精品课堂(人教A版2019必修第二册)