1 . 已知等比数列
的前
项和为
,
是等差数列,
,
,
,
.
(Ⅰ)求
和
的通项公式;
(Ⅱ)设
的前n项和为
,
,
.
(ⅰ)当n是奇数时,求
的最大值;
(ⅱ)求证:
.
![](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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdd3a25ac2cde3d2c884028f750cfff8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/684b935a7274130d081bfa7b2b938023.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c45994e58cc2032df1cc501e44ed17f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0b3874af2d1f4dcf456e5d24c4359a9.png)
(Ⅰ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(Ⅱ)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/7db76422e0e75880dab2c22b549e1323.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(ⅰ)当n是奇数时,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3b3820b14ec56411661ab328bb2ad17.png)
(ⅱ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e58924a1e6d16eff497407912c41fa5f.png)
您最近一年使用:0次
2021-05-11更新
|
835次组卷
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4卷引用:天津市宝坻区第一中学2020-2021学年高三上学期第四次月考数学试题
天津市宝坻区第一中学2020-2021学年高三上学期第四次月考数学试题天津市河东区第三十二中学2024届高三上学期第二次月考数学试题天津市和平区2021届高三下学期一模数学试题(已下线)天津市和平区2021届高三下学期第一次质量调查数学试题
名校
解题方法
2 . 已知数列
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)
,求对任意的正整数n都有
成立的k的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1575862605ff992ef5b8db9e1627243e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d4f231f556d4ae2a39cf38c76fc714d.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/25b67af73f586837594ab0db4b89baed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33305ffdb35723c9863523ac48cfc7bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da1275b12f777f1e88fbadc45dda6622.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea2140e0cd8aaffd8436ed5a20bf76f7.png)
您最近一年使用:0次
解题方法
3 . 已知正项数列
的前
项和为
,且
和
满足:
.
(1)求
的通项公式;
(2)设
,求
的前
项和
;
(3)在(2)的条件下,对任意
,
都成立,求整数
的最大值.
![](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/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7486d2d64adbff72a700b69a9a9d06ec.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d005409790b3192705a181b2c8e7dfed.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)
(3)在(2)的条件下,对任意
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dc555bfdcaf2bb5125410174daaffe6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
名校
解题方法
4 . 已知数列
的前
项和为
,满足
,数列
满足
,且
.
(1)证明数列
为等差数列,并求数列
和
的通项公式;
(2)若
,求数列
的前2n项和
;
(3)若
,数列
的前
项和为
,对任意的
,都有
,求实数
的取值范围.
![](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/deb64a2d5265b33d6c6727b956c9c29a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b0ac6e090846e97ccedd2f6d9168bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
(1)证明数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f997e6d483c0d0990cb550bbde39fa9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5b5eef03339913e27e0ce81d6f32b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbd85b79372dc6e596d465f738c3c300.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a17951c56a2ebe66ef13d08135ac0dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66d4e8502106802f1485c3b0f28f2664.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee6e88ac0b5133d7f51c7e166faf77e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
2021-08-17更新
|
782次组卷
|
10卷引用:天津市滨海新区七所重点学校2018届高三毕业班联考数学文科试题
天津市滨海新区七所重点学校2018届高三毕业班联考数学文科试题江苏省南通市启东中学2019-2020学年高二上学期第二次质检数学试题江苏省南通市启东中学2019-2020学年高二上学期第一次质量检测数学试题江苏省扬州市高邮中学2020-2021学年高二上学期9月月考数学试题(已下线)天津市七所重点学校2023届高三下学期3月联考文科数学试题天津市北辰区南仓中学2024届高三上学期教学质量过程性检测与诊断数学试题【全国校级联考】滨海新区七所重点学校2018届高三毕业班联考数学(文)试题天津市南开中学2021届高三下学期三模数学试题天津市市区重点中学2022届高三下学期三模数学试题四川省成都外国语学校2021-2022学年高二上学期入学考试数学(理)试题
5 . 对于无穷数列
,若
,
,则称数列
是数列
的“收缩数列”,其中
分别表示
中的最大项和最小项,已知数列
的前n项和为
,数列
是数列
的“收缩数列”
(1)若
求数列
的前n项和;
(2)证明:数列
的“收缩数列”仍是
;
(3)若
,求所有满足该条件的数列
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/641df1c74b500ec998622b756a173115.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f72dcd6cb9ea1a0c32a16e4914668bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e36bff57bcfa86432b340e25e51d42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e97b763ff0478b1bd535810c596b3cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6be5a8d331f694e083d67675e03d2af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/63d471926f7b27322d90c82b9ce21d3d.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61dfe50de35322cd725884838f004c95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1cebb9ccd8e2046a99c1473df04cca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
您最近一年使用:0次
2020-09-03更新
|
1077次组卷
|
4卷引用:天津市滨海新区塘沽第一中学2020-2021学年高三上学期第五次月考数学试题
6 . 已知数列
满足:
,
.
(1)设
,求证数列
为等比数列,并求数列
的通项公式;
(2)设
,数列
的前
项和为
,求证:
;
(3)设
,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1329f19710684b6d0acd70f9bac25d46.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85833965396eb183d024a03db9ca2735.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd42e8d3abc884c1bdea3e525abfbbc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.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/94351ce858fa3f3a09cfadc2d23d7253.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4acd47619b7b4d1f536014be98a38d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37a35110474d505740fee4f7488e9dd6.png)
您最近一年使用:0次
名校
解题方法
7 . 已知公差大于0的等差数列
的前n项和为
,且满足
,
.
(1)求数列
的通项公式
;
(2)若
,求
的表达式;
(3)若
,存在非零常数
,使得数列
是等差数列,存在
,不等式
成立,求k的取值范围.
![](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/1d4b9a84d8ffc48d254ed976c2667a36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc9ba415856ddd50bb4202d217bc931a.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b46156f515c26c96997054b141ed35b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15e4a9bdb1a7d858f6fddd7b1b5c1793.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.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/6834d7f86cf772f95864f2f7a6184028.png)
您最近一年使用:0次
2020-04-25更新
|
469次组卷
|
3卷引用:天津市耀华中学2020-2021学年高二上学期第二次阶段检测数学试题
名校
8 . 数列
中,
,且
,则当前
项和
最小时,
的值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee0f21c8ae101250f792de64e7aac822.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be29d8f996c54183663d8a954166dc16.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/b6a24198bd04c29321ae5dc5a28fe421.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2019-12-02更新
|
407次组卷
|
3卷引用:天津市第八中学2020-2021学年高二上学期第三次统练数学试题
名校
9 . 已知正项数列
的前
项和为
,数列
的前
项和为
,满足
,
,且
,
.
(1)求
,
的值,并求
的通项公式;
(2)若
对任意
恒成立,求实数
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0863cf59114f905e9ad3debc5572792.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15613df225de2600950d819544c357ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/954509b571b79f29c6c4471739b13ae9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
(1)求
![](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/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae42bb614d409324b8b8a4ccb15194be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
2019-06-12更新
|
388次组卷
|
2卷引用:【省级联考】浙江省2019年5月高二年级阶段性测试联考数学学科试题
名校
10 . 给定数列{cn},如果存在常数p、q使得cn+1=pcn+q对任意n∈N*都成立,则称{cn}为“M类数列”.
(1)若{an}是公差为d的等差数列,判断{an}是否为“M类数列”,并说明理由;
(2)若{an}是“M类数列”且满足:a1=2,an+an+1=3•2n.
①求a2、a3的值及{an}的通项公式;
②设数列{bn}满足:对任意的正整数n,都有a1bn+a2bn﹣1+a3bn﹣2+…+anb1=3•2n+1﹣4n﹣6,且集合M={n|
≥λ,n∈N*}中有且仅有3个元素,试求实数λ的取值范围.
(1)若{an}是公差为d的等差数列,判断{an}是否为“M类数列”,并说明理由;
(2)若{an}是“M类数列”且满足:a1=2,an+an+1=3•2n.
①求a2、a3的值及{an}的通项公式;
②设数列{bn}满足:对任意的正整数n,都有a1bn+a2bn﹣1+a3bn﹣2+…+anb1=3•2n+1﹣4n﹣6,且集合M={n|
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2019-06-12更新
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3卷引用:上海市上海交大附中2016届高三上学期摸底数学试题