1 . 在数列
中,
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa37e5661af68b263a3ed9030d4e9003.png)
__________ .
![](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/42933247035d56164dc3fe21f6f7eb97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c369e9f0c7c902ce7403137100514152.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa37e5661af68b263a3ed9030d4e9003.png)
您最近一年使用:0次
2023-02-06更新
|
350次组卷
|
4卷引用:安徽省芜湖市第一中学2018-2019学年高一下学期期中数学试题
名校
解题方法
2 . 已知
是等差数列
的前n项和,
,则
的值是( )
![](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/6993f692c624c2fac191912c63381cbc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/973d17cd50a4905164d29b8449fafd52.png)
A.60 | B.30 | C.15 | D.8 |
您最近一年使用:0次
2023-10-31更新
|
1358次组卷
|
3卷引用:天津市北辰区2020届高三上学期第一次联考(期中)数学试题
名校
解题方法
3 . 已知等差数列
中,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ccf71e2b479367c99bd6c1728b73cf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/554e6c461ccc5aa3093c524aa528a4e2.png)
A.11 | B.12 | C.13 | D.14 |
您最近一年使用:0次
2023-09-04更新
|
342次组卷
|
2卷引用:广西桂林市桂林中学2020-2021学年高二上学期期中数学(理)试题
解题方法
4 . 设数列
是公差不为零的等差数列,
,且
成等比数列.
(1)求数列
的通项公式及前
项和
;
(2)设
,求数列
的前
项和
.
![](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/2a18556fda4a825861f1170cdeb059ff.png)
(1)求数列
![](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)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb60d0866b63b2465624b34d718b32e.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
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)
您最近一年使用:0次
2023-03-08更新
|
597次组卷
|
13卷引用:金科大联考2020届高三5月质量检测数学(文科)试题
金科大联考2020届高三5月质量检测数学(文科)试题安徽省皖北名校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(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)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(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)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
解题方法
6 . 设等差数列
的前
项和为
,若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.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/526fa082e958551233ce1f9510eb6096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/185eb7967e13ada069ff64a009b07503.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
您最近一年使用:0次
2022-05-06更新
|
266次组卷
|
3卷引用:上海市虹口区2019-2020学年高三上学期期末数学试题
7 . 如果等差数列
中,
是它的前
项和,
,那么
( )
![](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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4250e3ff87622580f7e8923e3284891d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf14ebc775db2414a5a960badca8960.png)
A.14 | B.21 | C.28 | D.35 |
您最近一年使用:0次
8 . 已知数列
是等差数列,
,
.
(1)求数列
的通项公式;
(2)设
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/142efe0d1a51d7134b43e5fcd932c42b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e812feee5182e17f628b396b0c5afd.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9253eb4b892b8ae34fd6baf4b02460d5.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/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
2023-01-22更新
|
980次组卷
|
4卷引用:北京市十一学校2019-2020学年高一上学期期末数学试题
名校
9 . (1)在等差数列
中,已知
,求
;
(2)在等比数列
中,已知
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed0de0acd6f639f39856ba971d5f0837.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7eed39c7d611309b01476c15ab242308.png)
(2)在等比数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47a4797053624c5447806488756b2231.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
您最近一年使用:0次
10 . 已知
,把数列{an}的各项排成如图所示的三角数阵,记S(m,n)表示该数阵中第m行中从左到右的第n个数,则S(9,6)对应数阵中的数是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614b58b897d4ff2a62d0eac4e7e60d34.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/27/5a866e86-e03c-43d4-9d41-72a276b45f41.png?resizew=77)
您最近一年使用:0次