1 . 定义:在一个有穷数列的每相邻两项之间插入这两项的和,形成新的数列,我们把这样的操作称为该数列的一次“和扩充”,例如:数列
经过第一次“和扩充”后得到数列
;第二次“和扩充”后得到数列
.设数列
经过
次“和扩充”后得到的数列的项数为
,所有项的和为
.
(1)若
,求
;
(2)求不等式
的解集;
(3)是否存在数列
,使得数列
为等比数列?请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/680e9ef551b325387ab31dca1f893705.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa2d5ffc86bda25b7fd377267ae3e7df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef1d5a07307b7d2603995105ab2490f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f33d09c34e89bc99fbeb30bac80d4f90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a642ed9870f81d906816bc0db3d621c.png)
(2)求不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dcd08431daac10be93e6fafbc5d4a90.png)
(3)是否存在数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/863d3bc9596595b16499a46479526680.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/846fa57d92d6ad44d6a0cafad1e71ed4.png)
您最近一年使用:0次
2 . 已知数列
的前n项和为
,
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d82b7afbfc50eb2bbb34b8760071e8a0.png)
(1)求
;
(2)若
,求数列
的前1012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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d82b7afbfc50eb2bbb34b8760071e8a0.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08956de999dbddf9e42111a3d7cd9012.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ee6b547a3be248c012cc94abf603c09.png)
您最近一年使用:0次
2024-06-11更新
|
756次组卷
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5卷引用:甘肃省武威第六中学2023-2024学年高三下学期第五次诊断数学试卷
甘肃省武威第六中学2023-2024学年高三下学期第五次诊断数学试卷河南省九师联盟2024届高三下学期5月联考数学试题辽宁省沈阳铁路实验中学2024届高三第八次模拟考试数学试题(已下线)4.3.2等比数列的前n项和公式(2)(已下线)4.2.2等差数列的前n项和公式(1)
解题方法
3 . 对于数列
,定义
为
的“优值”,现已知某数列
的“优值”
,记数列
的前
项和为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e4b5a382f920203b9ef307224ae641e.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9682bbf19fb74219f2c6266bd35f5ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/466a22f3320bb2340bab262cab2d713e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cfb8091a44e1edbc4dc5274a57cbd0b.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/4e4b5a382f920203b9ef307224ae641e.png)
您最近一年使用:0次
解题方法
4 . 数列
的前n项和为
,设甲:
;乙:
为等差数列.则甲是乙的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f7c445e0b95cd5f4675706e007206c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46fdbb411d9943abe66011aa5dfc0f7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
A.充分不必要条件 | B.必要不充分条件 |
C.充要条件 | D.既不充分也不必要条件 |
您最近一年使用:0次
解题方法
5 . 设数列
的前n项和为
.
(1)求数列
的通项公式;
(2)设数列
的前n项和为
,且
,求
;
(3)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc273cca83b28805871da5e075d9982a.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](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/98c0250dcb2a000f60f3e38e5c6fdb92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02afb88e9f75094ff7a7918f0751dc14.png)
(3)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7807bf11e3310bf1c864eccf7138fb46.png)
您最近一年使用:0次
解题方法
6 . 数列
满足:
,则下列结论中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e244cad9e67669306a6996c5412e25ee.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
2024-04-16更新
|
1704次组卷
|
5卷引用:甘肃省兰州市第五十八中学2024届高三第二次高考仿真考试数学试题
甘肃省兰州市第五十八中学2024届高三第二次高考仿真考试数学试题湖北省黄冈八模2024届高三数学模拟测试卷(二)(已下线)第一套 艺体生新高考全真模拟 (二模重组卷)(已下线)第一套 艺体生新高考全真模拟 (二模重组卷1)河南省顶级名校2024届高三下学期高考考前全真模拟演练数学试题
7 . 在
个数码
构成的一个排列
中,若一个较大的数码排在一个较小的数码的前面,则称它们构成逆序(例如
,则
与
构成逆序),这个排列的所有逆序的总个数称为这个排列的逆序数,记为
,例如,
,
(1)计算
;
(2)设数列
满足
,求
的通项公式;
(3)设排列
满足
,求
,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a29d81c026773e88b4cd8e32291d3da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc77dfe095330d5ac22696e02745f4f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b066322d5ce7859e174207d32fdeb8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fb8280885d0fd1a072039e0bbcd15a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50bae0107d95c2964c862d83a78a7880.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c74b667cbad8dc6743f8f267be05880.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7eba82f58e8b21de76ba3822d72fdcc.png)
(1)计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34b2a92868a61502de7efffa97c5d433.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d52887aab7abbf479861ecbde18a095.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)设排列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1500f2f97c5b9f3ec287f585c47259eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfdd0eec263a21fcd5e7535c99eea1ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
2024-04-12更新
|
1705次组卷
|
8卷引用:甘肃省定西市2023-2024学年高三下学期教学质量统一检测数学试题
甘肃省定西市2023-2024学年高三下学期教学质量统一检测数学试题甘肃省靖远县2024届高三第三次联考试题三模数学试题广东省湛江市2024届高三下学期二模考试数学试题(已下线)数学(广东专用03,新题型结构)辽宁省葫芦岛市协作校2023-2024学年高三下学期第一次考试数学试卷辽宁省大连市第二十三中学2024届高三下学期校模拟考试数学试题(已下线)模块一专题3 数列的实际应用和综合问题单元检测篇A基础卷(高二人教B版)(已下线)模块一 专题4 数列的实际应用和综合问题单元检测篇A基础卷(高二北师大版)
解题方法
8 . 若一个平面多边形任意一边所在的直线都不能分割这个多边形,则称这样的多边形为凸多边形,凸多边形不相邻两个顶点的连线段称为凸多边形的对角线.用
表示凸
边形
对角线的条数.
(1)求数列
的通项公式;
(2)若数列
的前n项和为
,求数列
的前n项和
,并证明
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19c0cad05922d240afa9861ff4316a17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99805776dc637b33162e986b78f582dd.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef944f3ce43ee605543a328f6c0d4969.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/229b1290f1b0050f0c1decda7ee738ea.png)
您最近一年使用:0次
解题方法
9 . 已知数列的前
项和为
,且
.
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d81b57d696441836b63b25b2547b92d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
2024-03-25更新
|
2114次组卷
|
5卷引用:甘肃省白银市名校2023-2024学年高三下学期联合检测数学试题
名校
解题方法
10 . 已知数列
的前
项和为
,满足
;数列
满足
,其中
.
(1)求数列
的通项公式;
(2)对于给定的正整数
,在
和
之间插入
个数
,使
,
成等差数列.
(i)求
;
(ii)是否存在正整数
,使得
恰好是数列
或
中的项?若存在,求出所有满足条件的
的值;若不存在,说明理由.
![](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/83fd67e206753eff52406291c19daa38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f23f7f601ad9971d3de3e2dd820642e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0197eeeeaafec6b1fdd7bb8509572f6b.png)
(2)对于给定的正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd6f136f7c8d27b406c0993dcfece54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4b8d5b6045219ea4527202ab131bb2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/417083c7157cf0b45befc7c537f1012c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/629e172f62f389ea84b7d771c1c27566.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a039f1df440117fe89030a4ad6dcf291.png)
(i)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22be6bbf70b5c135edaf8db69118cb50.png)
(ii)是否存在正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d75ed0812322ed46d25ec41f609674be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
2024-03-19更新
|
2002次组卷
|
6卷引用:甘肃省白银市靖远县第四中学2024届高三下学期模拟预测数学试题