1 . 进位制是人们为了计数和计算方便而约定的记数方式,通常“满二进一,就是二进制;满八进一,就是八进制;满十进一,就是十进制……;满几进一,就是几进制”.
我们研究的正整数通常是十进制的数,因此,将正整数
的各位上的数字分别记为
,则
表示为关于10的
次多项式,即
,其中
,
,记为
,简记为
.
随着计算机的蓬勃发展,表示整数除了运用十进制外,还常常运用二进制、八进制等等.更一般地,我们可类似给出
进制数定义.
进制数的定义:给出一个正整数
,可将任意一个正整数
,其各位上的数字分别记为
,则
唯一表示为下列形式:
,其中
,
,并简记为
.
进而,给出一个正整数
,可将小数
表示为下列形式:
,其中
,
,并简记为
.
(1)设
在三进制数下可以表示为
,
在十进制数下可以表示为
,试分别将
转化成十进制数,
转化成二进制数;
(2)已知数列
的前
项和为
,且满足
,
,数列
满足,当
时,
;
①当
时,求数列
的通项公式;
②证明:当
时,
.
我们研究的正整数通常是十进制的数,因此,将正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23dd0a10a73674c8a47420d7e91da0cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432851e0d0b7a2924da29b9cc5ca1706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05c95c671f517c02f1deccd2174f7465.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f856d17cdd7499eeea956845fe51ad2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ceec6993cc9e39a5d5e6097d6447c6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35d5a7b02c9d7bd9e2910849ab591fc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/856f717993779ce676195ed3c8074e15.png)
随着计算机的蓬勃发展,表示整数除了运用十进制外,还常常运用二进制、八进制等等.更一般地,我们可类似给出
![](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/50e3273deabbf8c7d700d340b71ca2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45c89fe2197a7044536c5c3b52789636.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3f285903ef04eb7a1d2071cb7197521.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c22a19eeff39dff098ea766cf74d3c69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53d2aae1ce527125960613e78e1bb501.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2a4ce3547aff6aebdd145d11c566fe.png)
进而,给出一个正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e3273deabbf8c7d700d340b71ca2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20277d6743703a3710d6ceb8dc869cef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31ef1766237596595c550af4600c370e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8e6d4140fcd9583fe03f91701ae083f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74304131e01d0e9e68bd8a566b30d529.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b104090ea2ac34be58a76a4e0e95cb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99dc317d03cfed7687fad0448c298f9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7df1d9b712b639c8b6809c9f3ae03706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19d9abc918557b3bd56cb30dfd20b91f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b104090ea2ac34be58a76a4e0e95cb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7df1d9b712b639c8b6809c9f3ae03706.png)
(2)已知数列
![](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/fb451756eab7b736e0c576e03f6243b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/931b93e6ee1145e185621ae08dbf170f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26663935b7cb86ca81ad2aa73d49e26a.png)
①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/931b93e6ee1145e185621ae08dbf170f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
②证明:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/931b93e6ee1145e185621ae08dbf170f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac363332016ae0fa59a5e4a1d41e2a0b.png)
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2 . 已知等差数列
的前n项和为
,且
也是等差数列.
(1)求数列
的公差;
(2)若
,求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad971e3ee0d55b9838b3d6956407c651.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbe7bdaaf8b0adf10bf2ef6c1255b1dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba57c83d526ac308d1461e80fcca9f36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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名校
解题方法
3 . 在
中,内角
,
,
所对的边分别为
,
,
,
且
,
的外接圆半径为
.
(1)求
的面积;
(2)求
边
上的高
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.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/c5db41a1f31d6baee7c69990811edb9f.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/0334bc85843337c4dfcfdc5c638f9f62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8641de131e86041bb4cee948569cdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f83dbfddc6f98548699ed581e8c8608.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eabd5f3a86afe49dcd70571e2b96cfd.png)
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名校
4 . 某机构为了解2023年当地居民网购消费情况,随机抽取了100人,对其2023年全年网购消费金额(单位:千元)进行了统计,所统计的金额均在区间
内,并按
,
,
分成6组,制成如图所示的频率分布直方图.
的值,并估计居民网购消费金额的中位数;
(2)若将全年网购消费金额在20千元及以上者称为网购迷,结合图表数据,补全
列联表,并判断是否有
的把握认为样本数据中网购迷与性别有关系?说明理由.
下面的临界值表仅供参考:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/738562a008e41e8fad263220c1469beb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fefcf2ff128ca36765fc9b1854a4819c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4cb7beb1232e0b707b723934934692c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa148aedda1867a8994fa4b7637956ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若将全年网购消费金额在20千元及以上者称为网购迷,结合图表数据,补全
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b72fcdc709e77910cd36a26369648b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe157a9c3fe004a25bf1fb79c8c0a1b.png)
男 | 女 | 合计 | |
网购迷 | 20 | ||
非网购迷 | 47 | ||
合计 |
![]() | 0.15 | 0.10 | 0.05 | 0.025 | 0.010 | 0.005 | 0.001 |
2.072 | 2.706 | 3.841 | 5.024 | 6.635 | 7.879 | 10.828 |
(参考公式:,其中
您最近一年使用:0次
解题方法
5 . 为弘扬中华民族优秀传统文化,某校举行“阅读经典名著,传承优秀文化”闯关活动.参赛者需要回答三个问题,其中前2个问题回答正确各得5分,回答不正确得0分;第三个问题回答正确得10分,回答不正确得-5分,得分不少于15分即为过关.如果甲同学回答前两个问题正确的概率都是
,回答第三个问题正确的概率为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
(1)求甲同学过关的概率;
(2)求甲同学回答这三个问题的总得分X的分布列及数学期望.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
(1)求甲同学过关的概率;
(2)求甲同学回答这三个问题的总得分X的分布列及数学期望.
您最近一年使用:0次
解题方法
6 . 已知函数
的图象与
轴交于点
,且在
处的切线方程为
,记
.(参考数据:
).
(1)求
的解析式;
(2)求
的单调区间和最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc05f752a777614011647451889874cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a87dbf8a0849b60206932ca8e8401af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2b2f10a84d9700f906e4f8f74b0817.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b7843538ce5376655b5d4f269798af5.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/028517e8bebe634441e0a5c79828e88a.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18c49ca8562b98657ca9c499093f7233.png)
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名校
7 . 安徽省从2024年起实施高考综合改革,实行高考科目“
”模式.“2”指考生从政法、地理、化学、生物四门学科中“再选”两门学科,以等级分计入高考成绩.按照方案,再选学科的等级分赋分规则如下,将考生原始成绩从高到低划分为A,B,C,D,E五个等级,各等级人数所占比例及赋分区间如表1:
表1
将各等级内考生的原始分依照等比例转换法 分别转换到赋分区间内,得到等级分,转换公式为
,其中
分别表示原始分区间的最低分和最高分,
分别表示等级赋分区间的最低分和最高分,Y表示考生的原始分,T表示考生的等级赋分,计算结果四舍五入取整.若甲同学在五月全市模考中某选考科目成绩信息如表2(本次考试成绩均为自然数 )
表2
(1)求甲同学该科目的等级分;
(2)理论上当原始分区间
的极差
越大时,该区间中得分越低的同学赋分后等级分比原始分增加越多.比如某同学仅该科目较为薄弱,如果赋分后能比原始分增加9.5分以上(包含9.5分),那么六科总分排名相对于原始分排名就会有大幅提升,此时赋分制对于该同学就是有利的.经过统计数据,五月全市模拟考试该学科A等级的成绩分布如表3.则如果从A等级的学生中随机选出100名,X表示其中获益于赋分政策的人数,求
的值.
表3
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c8e63a3de229aa35d7e95b166802303.png)
表1
等级 | A | B | C | D | E |
人数比例 | ![]() | ![]() | ![]() | ![]() | ![]() |
赋分区间 | ![]() | ![]() | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6f2ad6e6581f5e97917d6b8ecc3af8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a7a53a5b7f3110a390396500f344386.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5dd698ddbe275267809650dc551e34.png)
表2
原始分 | 成绩等级 | 原始分区间 | 等级分区间 |
75分 | A等级 | ![]() | ![]() |
(1)求甲同学该科目的等级分;
(2)理论上当原始分区间
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4776c85b79df196f606d3ebf3697fbc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13502d46b8563c54c09b29b20b3006a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3c3a08851a75e5e879524978336d219.png)
表3
分数段 | ![]() | ![]() | ![]() | ![]() | ![]() |
人数比例 | ![]() | ![]() | ![]() | ![]() | ![]() |
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解题方法
8 . 已知各项均为正数的数列
前
项和为
,且
.
(1)求数列
的通项公式;
(2)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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/62dfbd34755b7fb668690c2173a32bda.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9acdd049cb1bf2b929dfdd30cc57b31d.png)
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9 . 在极坐标系中,曲线
的极坐标方程为
,曲线
的极坐标方程为
.
(1)若曲线
上一点的极角为
,求该点的极径;
(2)若曲线
与曲线
有公共点,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce7c2d17500ca2aaa810265e1c4a8140.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/424c5b900604a324617eb4ac00443818.png)
(1)若曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
(2)若曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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10 . 已知函数
.
(1)当
时,求
的最大值;
(2)求使
成立的
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c36837dfbf33fdbf59d497b60d0dd322.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef8634d2d5a531ebffd843f50644b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(2)求使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2623500ee20713f9a2555847f68bf1c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
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