解题方法
1 . 已知各项均为正数的两个数列
和
满足:
,
,
(1)设
,
,求证:数列
是等差数列;
(2)设
,
,且
是等比数列,求
和
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c3a2fd3a8d8473b7576b4060c11cd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/410332f96631d0fde958bba2357b4ee2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16ccfd5f9d8afdacef128bd713afdf38.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66480b05594886a986d035b0f038bea1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://img.xkw.com/dksih/QBM/2020/8/19/2531390791180288/2532618430078976/STEM/482468d531554381908077f8f69d600d.png?resizew=12)
您最近一年使用:0次
2018·上海浦东新·三模
名校
2 . 设
,若无穷数列
满足:对所有整数
,都成立
,则称
“
-折叠数列”.
(1)求所有的实数
,使得通项公式为
的数列
是
-折叠数列;
(2)给定常数
,是否存在数列
,使得对所有
,
都是
-折叠数列,且
的各项中恰有
个不同的值?证明你的结论;
(3)设递增数列
满足
.已知如果对所有
,
都是
-折叠数列,则
的各项中至多只有
个不同的值,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a949b947e9961d4d68bfeb4e24ef40f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98251cd3c3e36825493a3f83b0ac9d6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9cdd87bcc6088bea7dc1f24387b0502.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(1)求所有的实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6290fabfee064ca7296364c2011c16ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
(2)给定常数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/270672a95f2a5349bc440c53b5dd4a12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a949b947e9961d4d68bfeb4e24ef40f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dbc76e88046029a006e48b6b58823d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fbf39f278f6fcfbd30de4a1ad65e5bf.png)
(3)设递增数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4818b2c2d51316638cf39039d6cb4d11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f74927b7593fd0b4f218b3806e3025dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a949b947e9961d4d68bfeb4e24ef40f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681ae1522a36768618f7ddaf74abbb7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b037996f28c91402cff9c883c99a8e6.png)
您最近一年使用:0次
真题
名校
3 . 若无穷数列
满足:只要
,必有
,则称
具有性质
.
(1)若
具有性质
,且
,
,求
;
(2)若无穷数列
是等差数列,无穷数列
是公比为正数的等比数列,
,
,
判断
是否具有性质
,并说明理由;
(3)设
是无穷数列,已知
.求证:“对任意
都具有性质
”的充要条件为“
是常数列”.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e7146186b3a33ea5cbff137f9e3437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07c0b488096f27c73fc960e27f3b864a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73bc889cb3a977841028e444d62a4d09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e690b25af1cd3e04b784a9f26be3e90e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
(2)若无穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c522c1c881528ab6f9708f6bdd4c4db5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1e52d55280e664b707f4e9ef4cb1554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/928be44c53a39c116c715ab72f2f2d95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cb2db37e079b735acc41ea3035139e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2d8df5703574ef08007f1eea3cea18e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4611e6b3af6a0f44f9d7a481f0e50d72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
您最近一年使用:0次
2016-12-04更新
|
1002次组卷
|
16卷引用:《2018届优等生百日闯关系列》【江苏版】专题二 第五关 以子数列或生成数列为背景的解答题
(已下线)《2018届优等生百日闯关系列》【江苏版】专题二 第五关 以子数列或生成数列为背景的解答题(已下线)专题14 数列综合-五年(2016-2020)高考数学(文)真题分项(已下线)专题14 数列综合-五年(2016-2020)高考数学(理)真题分项(已下线)考点20 数列的综合运用-2021年高考数学三年真题与两年模拟考点分类解读(新高考地区专用)(已下线)重组卷03(已下线)专题21 数列解答题(理科)-22016年全国普通高等学校招生统一考试理科数学(上海卷精编版)北京市西城区北师大实验2017届高三上12月月考数学(理)试题北京西城北师大实验2017届高三上12月月考数学(理)试题上海市复旦大学附属中学2019届高三高考4月模拟试卷数学试题江苏省南通市海安高级中学2019-2020学年高三上学期9月月考数学试题北京市第八中学2021-2022学年高二下学期期中考试数学试题(已下线)2016年全国普通高等学校招生统一考试理科数学(上海卷参考版)2020年江苏省南通海安市高三学年初学业质量检测数学试题北京市中关村中学2022-2023学年高二下学期期中调研数学试题辽宁省沈阳市东北育才学校科学高中部2023-2024学年高二下学期期中考试数学试题
名校
4 . 已知二次函数
的图象的顶点坐标为
,且过坐标原点
.数列
的前
项和为
,点
在二次函数
的图象上.
(Ⅰ)求数列
的通项公式;
(Ⅱ)设
,数列
的前
项和为
,若
对
恒成立,求实数
的取值范围;
(Ⅲ)在数列
中是否存在这样一些项:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b338721e124048b547d3268a67ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edaaab658512ef8356e228879582cf94.png)
,这些项都能够构成以
为首项,
为公比的等比数列
?若存在,写出
关于
的表达式;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5f2932b9863fb218b7a990aa80abfc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.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/b8df5cca91bbd56bd8c68d3a9f87012e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
(Ⅰ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
(Ⅱ)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc0c5e305fdd6773ca9d5ce1d1fb4368.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/255afadbbd30a385b4a433f95b27962d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/851c8763f6700bccac95949fc0d316f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
(Ⅲ)在数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b338721e124048b547d3268a67ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edaaab658512ef8356e228879582cf94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b5423a1ef40732567e3b18098270f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a1cd8452683923f3fcade9034f78a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e956b81c5f97904f3d7c0843c717cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d55a7d201b7336a2b950c7fb05409bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
2016-12-03更新
|
1825次组卷
|
5卷引用:考向18 数列不等式-备战2022年高考数学一轮复习考点微专题(上海专用)
(已下线)考向18 数列不等式-备战2022年高考数学一轮复习考点微专题(上海专用)(已下线)专题17 数列探索型、存在型问题的解法 微点1 数列探索型问题的解法2015届北京市顺义区高三第一次统一练习(一模)理科数学试卷上海市行知中学2018-2019学年高三上学期期中数学试题江西省南昌八中、南昌二十三中等四校2018-2019学年高一下学期期中联考数学试题
5 . 已知数列
为等差数列,
,
的前
和为
,数列
为等
比数列,且
对任意的
恒成立.
(Ⅰ)求数列
、
的通项公式;
(Ⅱ)是否存在非零整数
,使不等式
对一切
都成立?若存在,求出
的值;若不存在,说明理由.
(Ⅲ)各项均为正整数的无穷等差数列
,满足
,且存在正整数k,使
成等比数列,若数列
的公差为d,求d的所有可能取值之和.
![](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/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/034ba25825c13725931c483aa47c9363.png)
比数列,且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eca8a0c2499f7a5e1860d23940cd87b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
(Ⅰ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(Ⅱ)是否存在非零整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0bc042352e2f4d4a5cc80492ad120d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(Ⅲ)各项均为正整数的无穷等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc25e825ee0cd0b1708aa39349468716.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b78bf40d71329e4898bd227324173cc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
您最近一年使用:0次
真题
6 . 已知
是公差为
的等差数列,
是公比为
的等比数列.
(1) 若
,是否存在
,有
说明理由;
(2) 找出所有数列
和
,使对一切
,
,并说明理由;
(3) 若
试确定所有的
,使数列
中存在某个连续
项的和是数列
中的一项,请证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(1) 若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ab4ad049f59b28b6f434b5933af5a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e396eb470cb5c41cb751391e3dc1ea5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/523764272014175d85c35e1b85ef3e80.png)
(2) 找出所有数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09fee32e0d09ea30addd230ef4c972a5.png)
(3) 若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8676c526f1aedf8acba91cb42e21602f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
您最近一年使用:0次
2016-11-30更新
|
1757次组卷
|
3卷引用:考向16 数列求和及数列的综合应用-备战2022年高考数学一轮复习考点微专题(上海专用)
(已下线)考向16 数列求和及数列的综合应用-备战2022年高考数学一轮复习考点微专题(上海专用)沪教版(上海) 高三年级 新高考辅导与训练 第四章 数列与数学归纳法 二、数列的其他问题2009年普通高等学校招生全国统一考试理科数学(上海卷)
名校
7 . 设数列
满足
,其中
,且
,
为常数.
(1)若
是等差数列,且公差
,求
的值;
(2)若
,且存在
,使得
对任意的
都成立,求
的最小值;
(3)若
,且数列
不是常数列,如果存在正整数
,使得
对任意的
均成立. 求所有满足条件的数列
中
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b4c63e894402368c2d3ccc41fb53205.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bc5735838e43b7a229e8f45c9bfffb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac69e6db1df13ed64756b4f391ae9fac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/812be9806122241c476ba1db516c4823.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfc23f793ac06643cfc07e01eb205aa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d7448e65bda478cce0c6092e2c9eff7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f1a89ad1646a6d4fcdcf1bc84414201.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78fbecca12ee62538020483fd55a2109.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b2b94cbf8f1acc77ed2618d9ba5756a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
您最近一年使用:0次
2018-01-18更新
|
715次组卷
|
7卷引用:2018年高考二轮复习测试专项【苏教版】专题六 不等式
(已下线)2018年高考二轮复习测试专项【苏教版】专题六 不等式(已下线)《2018届优等生百日闯关系列》【江苏版】专题二 第五关 以子数列或生成数列为背景的解答题南京市、盐城市2018届高三年级第一次模拟考试数学(理)试题上海市格致中学2018-2019学年高三下学期3月月考数学试题2020届江苏省南通市如东县栟茶高级中学高三上学期第三次月考数学试题上海市七宝中学2022届高三冲刺模拟卷二数学试题江苏省南京市六校2024届高三下学期期初联合调研数学试题
名校
8 . 已知数列
满足:
(其中
且
),
为数列
的前
项和.
(1)若
,求
的值;
(2)求数列
的通项公式
;
(3)当
时,数列
中是否存在三项构成等差数列,若存在,请求出此三项;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84e4a6ba8df6cbe80b09da11a40df0bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78fbecca12ee62538020483fd55a2109.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9805d9c45198c7a249f317222f564999.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2251391555522aa9598f3c6587c011f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(3)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1c3ea872a20fdc1843cb5ffce8a554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次