解题方法
1 . 设
是等差数列
的前n项和,且
,
,则公差
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0078f6d65d99ed5ac0bf789fbf87348f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2cb4485663835fc40a9cf82f491d5b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
A.1 | B.2 | C.5 | D.6 |
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2卷引用:陕西省西安市周至县2020-2021学年高三一模文科数学试题
2 . “垛积术”在我国古代早期主要用于天文历法,后来用于求高阶等差级数的和.元代数学家朱世杰在沈括(北宋时期数学家)、杨辉(南宋时期数学家)研究成果的基础上,在《四元玉鉴》中利用了“三角垛”求一系列重要的高阶等差级数的和.例如,欲求数列
,
,
,…,
,
的和,可设计一个正立的
行三角数阵,即正三角形
的区域中所有数的分布规律为:第1行为1个
,第2行为2个
,第3行为3个
,…,第
行为
个1;再选一个数列
(其前
项和已知),可设计一个倒立的
行三角数阵,即正三角形
的区域中所有数的分布规律为:第1行为
个
,第2行为
个
,第3行为
个
,…,第
行为1个1.这两个三角数阵就组成一个
行
列的菱形数阵.若已知
,则运用垛积术,求得数列
,
,
,…,
,
的和为____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d8d28c824b791078bd9e60a636cebd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6780dd20734ecb6865a4ec9bae255b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1025927646fd51373b385bb5ed9dceb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94613fe8f9b0fc1ba68e541a1ddad6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56eb12f6196469a8d1e556cb0fab6085.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a1271285428c740905f7d5db68c5dc6.png)
![](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/3ab8a7e95d65fd5fcb3650297ec75a9c.png)
![](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/7f9e8449aad35c5d840a3395ea86df6d.png)
![](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/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a1271285428c740905f7d5db68c5dc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a1271285428c740905f7d5db68c5dc6.png)
![](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/7a0876215b2fd463d151523cd3c6b447.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6921dc242c40a1d342e3b033fc3aa9c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d8d28c824b791078bd9e60a636cebd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6780dd20734ecb6865a4ec9bae255b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1025927646fd51373b385bb5ed9dceb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94613fe8f9b0fc1ba68e541a1ddad6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56eb12f6196469a8d1e556cb0fab6085.png)
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7卷引用:贵州省盘州市2021届高三第一学期第一次模拟考试理科数学试题
贵州省盘州市2021届高三第一学期第一次模拟考试理科数学试题(已下线)热点04 数列求和及综合应用-2022年高考数学【热点·重点·难点】专练(全国通用)(已下线)第三篇 数列、排列与组合 专题2 多边形数、伯努利数、斐波那契数、洛卡斯数、明安图数与卡塔兰数 微点2 多边形数综合训练(已下线)专题11 数列前n项和的求法 微点1 公式法求和(已下线)专题18 数列中的创新题的解法 微点2 数列中的创新题综合训练福建省莆田第五中学2023-2024学年高二下学期第一次月考数学试卷(已下线)模块三 失分陷阱2 不会从情境中抽出数列模型或关系
名校
3 . 在等差数列
中,
,则数列
的前11项和
=___ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0480cd79f8ee3b685c896fa45fd55ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b87df689b605e7a283b56d454c3736a0.png)
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10卷引用:宁夏中卫市2021届高三二模数学(文)试题
宁夏中卫市2021届高三二模数学(文)试题江苏省2020届高三下学期高考压轴卷数学试题(已下线)卷01-【赢在高考·黄金20卷】备战2021年高考数学全真模拟卷(北京专用)四川省成都市第七中学2020-2021学年高二下学期理科数学3月阶段性考试试题河南省实验中学2023届高三模拟考试四文科数学试题四川省成都市锦江区嘉祥外国语高级中学高2023届高三下学期三诊模拟考试数学(文科)试题文科数学-【名校面对面】河南省三甲名校2023届高三校内模拟试题(四)西藏自治区拉萨市拉萨那曲第二高级中学2019-2020学年高二上学期期中数学试题江苏省扬州市邗江区蒋王中学2019-2020学年高三下学期3月检测数学试题上海市四校(复兴中学、奉贤中学、金山中学、松江二中)2023届高三下学期3月联考数学试题
4 . 已知数列
是递增数列,
,且
.若
,则正整数
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/524f2313bf15c276605f916405b4d847.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90862eca0071c91262a7729c94642b66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd707b69a11f8de5566f23c1a2a9ff5a.png)
A.9 | B.10 | C.11 | D.12 |
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名校
解题方法
5 . 已知等差数列
中,
,
.
(1)求数列
的通项公式.
(2)记数列
的前
项和为
,证明
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/117dd04afc6d1a34828c7f9da7663a56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59d3c3f8e2e4003eefda164fb11c1444.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记数列
![](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/0031136b88c5c677de5ab4b3c74b7388.png)
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13卷引用:四川省绵阳第一中学2021届高三一诊适应性考试数学(理)试题
四川省绵阳第一中学2021届高三一诊适应性考试数学(理)试题金科大联考2020届高三5月质量检测数学(文科)试题(已下线)拓展二 数列求和的方法(精练)-2020-2021学年一隅三反系列之高二数学新教材选择性必修第二册(人教A版)安徽省皖北名校2020-2021学年高二上学期第一次联考数学试题河南省豫西名校2020-2021学年高二10月联考数学试题(已下线)第六单元 数列(B卷 滚动提升检测)-2021年高考数学(文)一轮复习单元滚动双测卷河南省洛阳市豫西名校2020-2021学年第一次联考高二数学试题陕西省宝鸡市教育联盟2020-2021学年高三上学期第二次月考理科数学试题陕西省宝鸡市教育联盟2020-2021学年高三上学期第二次月考文科数学试题(已下线)专题6-2 数列求和15种类型归纳-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)陕西省西安交通大学第二附属中学(南校区)2020-2021学年高三上学期10月月考理科数学试题河南省豫西名校2022-2023学年高二上学期第一次联考数学试题青海省西宁市大通县第一中学2024届高三第二次月考数学文科试题
名校
6 . 设等比数列
的前n项和为Sn,若
,
,
成等差数列,且
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05201ef79a5d5904f492845396fb5470.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48e81b54f78b96294295542b010dfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e91dcd541e3ba2ea6311906c3d5cf39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d211c5a622d0be3b39931d814f9a683.png)
A.-1 | B.-3 | C.-5 | D.-7 |
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5卷引用:云南省曲靖市第一中学2021届高三高考复习质量监测卷(八)数学(理)试题
云南省曲靖市第一中学2021届高三高考复习质量监测卷(八)数学(理)试题河北省深州市长江中学2022届高三上学期期中数学试题(已下线)专题07 数列的通项与数列的求和(练)--第一篇 热点、难点突破篇-《2022年高考数学二轮复习讲练测(新高考·全国卷)》青海省西宁市海湖中学2022-2023学年高三上学期期末考试数学(理)试题(已下线)专题16 等比数列-1
7 . 已知数列
:1,
,
,3,3,3,
,
,
,
,
,
,即当
(
)时,
,记
(
).
(1)求
的值;
(2)求当
(
),试用
、
的代数式表示
(
);
(3)对于
,定义集合
是
的整数倍,
,且
,求集合
中元素的个数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbd40e04e2a943051fa83d6e511add.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbd40e04e2a943051fa83d6e511add.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbd40e04e2a943051fa83d6e511add.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbd40e04e2a943051fa83d6e511add.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37e5531913e2f170465d8df01795cd51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/123374c62330ca2583f96688e9c27005.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a20fadc7f410eb813783eb020917bd1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf5776ec7059c208daf01ca48a34915.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86a9f96597f4006f719b1a14960a8de7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0ca3befd6622638091e99d273129d0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e145b6046bc80d0ffecc61ac67c87ca1.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6f422edb72f7e1d5529a5570feb77df.png)
(2)求当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6253e1e64cc4b92de299d498fe5e2f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cad52924df9291d5d191d18e09374ee1.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
(3)对于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d717b62cf19a284dacacfb596fc1d9dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61956a89366cc668a96692ad35b29b75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e145b6046bc80d0ffecc61ac67c87ca1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9852fbf13513943d251134cde29c3465.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/391d23b5ffaf0444a1d1a1550a0f3527.png)
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|
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5卷引用:上海市华东师范大学第二附属中学2021届高三下学期5月高考模拟数学试题
(已下线)上海市华东师范大学第二附属中学2021届高三下学期5月高考模拟数学试题上海市南洋模范中学2023-2024学年高二上学期开学考数学试题上海民办南模中学2023-2024学年高二上学期9月月考数学试题(已下线)专题22 新高考新题型第19题新定义压轴解答题归纳(9大核心考点)(讲义)(已下线)微考点4-1 新高考新试卷结构压轴题新定义数列试题分类汇编
名校
解题方法
8 . 已知等差数列
的公差为正数,
,前
项和为
,数列
为等比数列,
,且
,
.
(1)求数列
、
的通项公式;
(2)令
,求数列
的前
项的和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/385275d29d8c8a7841eaeaa3dfab2cdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4802639246aff10e070cec83a0c51baa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cc5db45d0261ac8cb2124e8e72c3755.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe62436d804004c3493b375054a50608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d51f9147b8265c0276c1f2c2659197.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbd85b79372dc6e596d465f738c3c300.png)
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2023-01-04更新
|
1130次组卷
|
4卷引用:天津市宁河区芦台第一中学2020-2021学年高三下学期第一次模拟考试数学试题
天津市宁河区芦台第一中学2020-2021学年高三下学期第一次模拟考试数学试题(已下线)模块九 数列-2浙江省金华十校2023-2024学年高三上学期11月月考模拟数学试题(已下线)黄金卷07(2024新题型)
名校
解题方法
9 . 已知数列
的前
项和为
, 且
, __________.请在
成等比数列;
, 这三个条件中任选一个补充在上面题干中, 并解答下面问题.
(1)求数列
的通项公式;
(2)设数列
的前
项和
, 求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/751c3b0c7d916ddc24d7bd036ea0eecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4011c597ba394120a1a74b6f4a401159.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25108967f8f95c445c109348592d4fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff3432f48e3f2e684d45e89403110ea9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9694346716bad8031f17fff37273ddc.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/751c3b0c7d916ddc24d7bd036ea0eecd.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55f3cadcc65d380f74102037b46a4f8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59887a5ab83d604d78b8a204b7f88bdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24974f2d84f24c6dc2d836e0d9fa5359.png)
您最近一年使用:0次
2022-12-26更新
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849次组卷
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7卷引用:四川省南充市2021-2022学年高三高考适应性考试(一诊)数学(理)试题
四川省南充市2021-2022学年高三高考适应性考试(一诊)数学(理)试题湖南省岳阳市2022届高三下学期教学质量监测(三)数学试题四川省遂宁市第二中学校2023届高三上学期一诊模拟考试理科数学试卷(二)(已下线)热点07 数列与不等式-2022年高考数学【热点·重点·难点】专练(新高考专用)(已下线)数列求和广东省揭阳市普宁国贤学校2022-2023学年高二上学期期末数学试题山西省晋城市泽州县晋城一中教育集团南岭爱物学校2022-2023学年高二上学期1月期末调研考试数学试题
名校
解题方法
10 . 已知正项等比数列
满足
,
,数列
满足
.
(1)求数列
,
的通项公式;
(2)令
求数列
的前n项和
.
(3)设
的前n项和为
,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2236a07e10adbeb10ddf296078605615.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4214eaf20248c5108c3ca78e93a460a7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9221c0c92a526f65533cdc5400767af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29240fe94ece0f3bf7aa01eb848d3e57.png)
您最近一年使用:0次
2022-12-20更新
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686次组卷
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3卷引用:天津市静海区第一中学2021届高三下学期二模数学试题