23-24高三上·北京西城·期末
名校
解题方法
1 . 给定正整数
,已知项数为
且无重复项的数对序列
:
满足如下三个性质:①
,且
;②
;③
与
不同时在数对序列
中.
(1)当
,
时,写出所有满足
的数对序列
;
(2)当
时,证明:
;
(3)当
为奇数时,记
的最大值为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad2477167a02872167b2a3760f09d6ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dc25d4213ca2eadce49e6d8ba805e15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1b730e2023809495f2bd7fbf48f07a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca986e62ec3a6e50e4e2cad639aa9201.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd869b784314b8278f5d144b2d3a9fb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/698c4d4e50062b4a7dd70fe1b4ab4fd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/302391681aa37ac20d6f533dbae9e137.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a215612787e43d28bfebc840c3903b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8a3cc8c48bf54ec8252e5dce6867754.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87a60302649eb940748da818199e55da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/241d587c2e6f2f109a4e41b79f1c800f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/926c16dd072c9ff8a560b003cfb47053.png)
(3)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4546b12ff89d1599427da82294afc09b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4546b12ff89d1599427da82294afc09b.png)
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2024-01-19更新
|
2089次组卷
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6卷引用:北京市西城区2024届高三上学期期末数学试题
(已下线)北京市西城区2024届高三上学期期末数学试题北京市西城区2024届高三上学期期末数学试题(已下线)高三数学开学摸底考 (北京专用)2024年普通高等学校招生全国统一考试数学冲刺卷二(九省联考题型)江西省南昌市第二中学2024届高三“九省联考”考后适应性测试数学试题(四)江苏省连云港高级中学2023-2024学年高二下学期第一次月考数学试卷
名校
2 . 已知当
时,
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e10245aa9aa362178f8f8cc0ceaf134.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
2023-04-02更新
|
2304次组卷
|
6卷引用:山西省三重教育2023届高三下学期3月联考数学试题
3 . 已知数列
的前
项和为
,且
对于
恒成立,若定义
,
,则以下说法正确的是( )
![](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/204fe825361c413ddc828c5505476789.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cac657ea5bbf4b237a30e4074c76cc81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac64b041aafdf33ee9816f4d70175a1c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8665563867d19ec3a09ba96cabb0a8f4.png)
A.![]() | B.![]() |
C.![]() | D.存在![]() ![]() |
您最近一年使用:0次
2022-04-07更新
|
2506次组卷
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7卷引用:湖北省二十一所重点中学2022届高三下学期第三次联考数学试题
湖北省二十一所重点中学2022届高三下学期第三次联考数学试题(已下线)考点13 数列概念及通项公式(核心考点讲与练)-2023年高考数学一轮复习核心考点讲与练(新高考专用)粤湘鄂名校联盟2023届高三上学期第一次联考数学试题(已下线)山东省青岛第二中学2022-2023学年高三上学期1月期末测试数学试题变式题11-16江苏省南京市第一中学2023届高三下学期2月期初考试数学试题山东省菏泽市菏泽一中八一路校区2024届高三上学期12月月考数学试题河南省焦作市博爱县第一中学2024届高三下学期4月月考数学试题
名校
解题方法
4 . 小林同学喜欢吃4种坚果:核桃、腰果、杏仁、榛子,他有5种颜色的“每日坚果”袋.每个袋子中至少装1种坚果,至多装4种坚果.小林同学希望五个袋子中所装坚果种类各不相同,且每一种坚果在袋子中出现的总次数均为偶数,那么不同的方案数为( )
A.20160 | B.20220 | C.20280 | D.20340 |
您最近一年使用:0次
2022-04-07更新
|
4236次组卷
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11卷引用:湖北省二十一所重点中学2022届高三下学期第三次联考数学试题
湖北省二十一所重点中学2022届高三下学期第三次联考数学试题(已下线)2022年高考考前20天终极冲刺攻略(三)【数学】(新高考地区专用)(6月1日)(已下线)2022年高考考前20天终极冲刺攻略(四)【理科数学】 (6月1日)(已下线)高二数学下学期期末精选50题(压轴版)-2021-2022学年高二数学考试满分全攻略(人教A版2019选修第二册+第三册)湖北省九校教研协作体2023届高三上学期起点考试数学试题(已下线)专题12 计数原理(理)(已下线)专题10-1 排列组合20种模型方法归类-3安徽省定远中学2023届高三下学期6月高考预测数学试卷(已下线)专题18 排列组合与二项式定理(已下线)计数原理与排列组合(已下线)6.2.3组合-6.2.4组合数——课时作业(提升版)
名校
5 . 设整数数列
,
,…,
满足
,
,且
,
,则这样的数列的个数为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e35eeaabd951fb09b2926807da3685b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a91870d50905112295ccb9287ebb8f02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7595888a4f3632ac396247d7012dd998.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71481243c145e96b64017f86b74143ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff3f51902e1270db756839c94ce7ec5.png)
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2021-10-14更新
|
1294次组卷
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5卷引用:上海市2022届高三上学期一模暨春考模拟卷(三)数学试题
上海市2022届高三上学期一模暨春考模拟卷(三)数学试题(已下线)专题12 计数原理(理)上海市格致中学2023届高三上学期12月月考数学试题(已下线)专题9-3 排列组合19种归类(理)(讲+练)-4(已下线)6.2.3组合-6.2.4组合数——课时作业(提升版)
6 . 已知集合
,集合
,
…
(
,
)都是集合A的子集.如图,作m行
列数表,其中第k行第l列的数为
.
记
,
;
,
;
对于m,n和
,若存在集合
,
…
满足下列条件:
①
;
②
;
③对任意的
,
的元素个数均为t.
则称有序数组
是相容的.
(1)求出所有相容的有序数组
;
(2)若
是相容的,请直接给出t的值,并给出一个满足条件的数表.
(3)求出所有相容的有序数组
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94d5fd428461ee4d35b58ec8aa2b10c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0d7559d8dfa8236ca9d4b1853fbdec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/338947df86eb08f890be799504afe309.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72ac49ab7c8001c209b8611b9ea40d85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d51f9147b8265c0276c1f2c2659197.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/536e055e0e772f3b1531979b2a4e5b11.png)
1 | 2 | … | ||
… | ||||
… | ||||
… | … | … | … | … |
… |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89adf9a240218bdb2e7e9b2a113fbb0d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a65bad3343f0e29460ead5b54771f362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d5181d80f92bb571b06ce5c6a0ea94b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e2dfdb35e79247dc2503a20a2f733f9.png)
对于m,n和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fec9cc98eb87065cb1b0982c0963233.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0d7559d8dfa8236ca9d4b1853fbdec.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e9d14acd6818b6c2680e697532ba69.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9d5fa697c5d54ef68407187bb7ffeb3.png)
③对任意的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebd42fc2af57877e06f485b50ae4d87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41e1766af890659ac91f4ed407f5a0f.png)
则称有序数组
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/275b49a943823f4cd63a32c5bbfcd43d.png)
(1)求出所有相容的有序数组
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b93f97d56675c9f658648655a4d19455.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffd39efc37b313c46be37698440ece2f.png)
(3)求出所有相容的有序数组
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e434a00127c271aee98ff92cda72b8.png)
您最近一年使用:0次
7 . 口袋中有大小、形状、质地相同的两个白球和三个黑球.现有一抽奖游戏规则如下:抽奖者每次有放回的从口袋中随机取出一个球,最多取球2n+1(n
)次.若取出白球的累计次数达到n+1时,则终止取球且获奖,其它情况均不获奖.记获奖概率为
.
(1)求
;
(2)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bec1b383f61d7a71f10ce999c9321381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18adc4ec9010e1e99b882761e9c2c2e.png)
您最近一年使用:0次
2020-06-05更新
|
1873次组卷
|
4卷引用:江苏省南京市2020届高三下学期6月第三次模拟考试数学试题
江苏省南京市2020届高三下学期6月第三次模拟考试数学试题(已下线)专题10-2 概率压轴大题(理)-2022年高考数学毕业班二轮热点题型归纳与变式演练(全国通用)湖北省九校教研协作体2022-2023学年高二上学期9月联考数学试题(已下线)4.1.3独立性与条件概率的关系(2)
12-13高一上·北京·期末
名校
8 . 已知集合
,若集合
,且对任意的
,存在
,
,使得
(其中
),则称集合
为集合
的一个
元基底.
(1)分别判断下列集合
是否为集合
的一个二元基底,并说明理由;
①
,
;
②
,
.
(2)若集合
是集合
的一个
元基底,证明:
;
(3)若集合
为集合
的一个
元基底,求出
的最小可能值,并写出当
取最小值时
的一个基底
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/806fb311a1ddd23364eb67dc6eaf9aee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb33db56afdfe2e6b023d001b8c7314.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dab92728b35ed5798e07a2b0095bfcc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a347b942334e794abc5d1a583e8b434d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64950c9fd9dc31394b2e00401d1b70ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29ad20a92aea25d3d1800ec6cb93699c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(1)分别判断下列集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5453c0f95e052beb1edece487d9cab07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/522954ce536d559cf03638d87fad504c.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca4863b95f36a4af59514b7c77e02e30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3757ba09c1d5ceb4632a8ddd47230902.png)
(2)若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2413015bd5826b340903708cc7750a0b.png)
(3)若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc98f4e6c9f9a1dc1080d0e0998fc99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
您最近一年使用:0次
2023-03-22更新
|
1034次组卷
|
15卷引用:2011-2012学年北京市育园中学高一第一学期期末考试数学
(已下线)2011-2012学年北京市育园中学高一第一学期期末考试数学北京市第二中学2020-2021学年高一下学期期末数学试题北京市清华大学附属中学2022届高三下学期数学统练6试题北京市丰台区丰台第二中学2023届高三上学期12月月考数学试题上海市进才中学2020-2021学年高二下学期期末数学试题(已下线)北京市第四中学2023届高三阶段性考试(零模)数学试题北京市汇文中学教育集团2022-2023学年高二下学期期中考试数学试题北京市广渠门中学2022-2023学年高二下学期期中考试数学试题北京市第五十七中学2022-2023学年高二下学期期中测试数学试题北京市第二中学2022-2023学年高二下学期第六学段(期末)考试数学试题(已下线)上海高二下学期期末真题精选(压轴60题35个考点专练)-【满分全攻略】2022-2023学年高二数学下学期核心考点+重难点讲练与测试(沪教版2020选修一+选修二)(已下线)难关必刷01集合的综合问题(3种题型40题专项训练)-【满分全攻略】(人教A版2019必修第一册)(已下线)计数原理与排列组合【北京专用】专题05计数原理(第二部分)-高二上学期名校期末好题汇编(已下线)专题01 数列(6大考点经典基础练+优选提升练)-【好题汇编】备战2023-2024学年高二数学下学期期末真题分类汇编(新高考专用)
9 . 考查
所有排列,将每种排列视为一个
元有序实数组
,设
且
,设
为
的最大项,其中
.记数组
为
.例如,
时,
;
时,
.若数组
中的不同元素个数为2.
(1)若
,求所有
元有序实数组
的个数;
(2)求所有
元有序实数组
的个数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb30e150b60cac09a03dd1fb72eb7941.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b82d71dc477a538b05de6574c91868e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/233427826eb2233641fc3a9805f6d206.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22dc54af0d6400579485cbd4e59ac9df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4af42989d172bdc7bfe1cf28822189b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47a84b137ec7bdb19c578ebd079b48c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58fbae1f3d87579b58c64f4768a871eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c7d2e9ce6efea9061ecff3607f10cb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/460410988196e1cdd34c08027766187a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01dbd048c482be3b79e926b66e56062f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fac3649308b528fd56545ba102dc42d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b82d71dc477a538b05de6574c91868e7.png)
(2)求所有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b82d71dc477a538b05de6574c91868e7.png)
您最近一年使用:0次
10 . 已知数列
,
,…,
的项
,其中
…,
,
,其前
项和为
,记
除以3余数为1的数列
,
,…,
的个数构成的数列为
,
.
(1)求
的值;
(2)求数列
的通项公式,并化简.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/477a1ff38aabe1a29f5bccd63500f339.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fcd8c5ff000f78cf14b0db5cf00a742.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6870663c08a264a61ced4f12957fcf46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08708dbc4cd3b098e0646d62f305681c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08708dbc4cd3b098e0646d62f305681c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3bf6071c209699ee6bd8e6199164617.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3bf6071c209699ee6bd8e6199164617.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/477a1ff38aabe1a29f5bccd63500f339.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
您最近一年使用:0次