名校
1 . 已知
为等差数列,若
,
,则
的值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7da6e97248df8f138ebe684c40c950c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2017-11-12更新
|
240次组卷
|
4卷引用:云南省下关第一中学2020-2021学年高二上学期段考(二)数学(文)试题
13-14高一下·广东佛山·期中
名校
2 . 已知等差数列
的通项公式
,则
等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://img.xkw.com/dksih/QBM/2012/11/23/1571067335925760/1571067340955648/STEM/55d9ffe0ecfe4d71a7021444159e851a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ccb15407a714486b937cffd69b4f9bb.png)
A.1 | B.2 | C.0 | D.9 |
您最近一年使用:0次
名校
3 . 等差数列
中,
,前11项的和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a9060f9833fdc330f9c12afe889dc41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6df1038200f2d97a52c716aab6c3bcb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a9060f9833fdc330f9c12afe889dc41.png)
A.10 | B.12 | C.14 | D.16 |
您最近一年使用:0次
2017-11-13更新
|
380次组卷
|
2卷引用:云南省玉溪第一中学2018届高三上学期第三次月考数学(文)试题
13-14高三上·江西·阶段练习
4 . 已知等差数列
的公差和首项都不等于0,且
,
,
成等比数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da9af8fbf2851478dc39a08841f0b633.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7da2f386b78cdf6489efaa2f5820d3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da9af8fbf2851478dc39a08841f0b633.png)
A.2 | B.3 | C.5 | D.7 |
您最近一年使用:0次
5 . 已知数列
满足:
,
,
.
(1)证明:数列
为等差数列,并求出数列
的通项公式;
(2)记
,求数列
的前n项和
.
![](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/3afe09c61a939e087f5da0c15f710cfa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(1)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41cf1da18d91f7c98086553d157d1a87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4cecbdebeb5d12fbe1d54b81cc05a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
6 . 已知等差数列
中,
且前10项的和为
,则数列
的公差![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b6f7d57dd0112421d63b0891acbf3fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/751859e4f0b1cb2c94fd5cca373de9af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
您最近一年使用:0次
7 . 等差数列
中,
,从第10项开始为正数,则公差
的取值范围是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a44e46d9f748ebbe2f91405d9cae178.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
12-13高二下·云南玉溪·期末
8 . 已知公差不为零的等差数列
的前
项和为
,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6859fba6df5a80b12bc11889aa6656e6.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/ed253514c9165a900976fc842c869270.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6859fba6df5a80b12bc11889aa6656e6.png)
您最近一年使用:0次