解题方法
1 . 已知数列
的前
项和
.
(1)求数列
的通项公式,判断这个数列是否是等差数列,并说明理由;
(2)记数列
的前
项和为
,若
,求
.
![](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/b2a1e12cb5d8e7677a1c9aae0d7ca1ae.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(2)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e73dc2f6f98a95893c1185dfb9572535.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/9580e608e2fcc7d114bd931d91befd13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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2 . 已知等差数列
的前
项和为
,公差
,且
成等比数列.
(1)求
;
(2)若
,数列
的前
项和为
,求
.
![](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/7b333f65402a5eacf1e903ef73108845.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb74a48df5b86edf1148fe35269d622f.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3a6581958ceecca3d4a8e6247dd5103.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/00136ab4fd69ba9c28b47cd38442dc3a.png)
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解题方法
3 . 已知函数
,记等差数列
的前
项和为
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b50ec7342673cc1f11b613c3efd3c6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
_______
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2291552257d1b9a796600771a47fa378.png)
![](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/97102be5034a0ad1868196d88e328739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b29cbfd5b18d7eb286de6ea95f87598.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b50ec7342673cc1f11b613c3efd3c6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
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|
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|
3卷引用:【名校面对面】2022-2023学年高三大联考(5月) 理数试题
4 . 记
为等差数列
的前
项和,已知
,且
为
与
的等比中项.
(1)求数列
的通项公式;
(2)若
,求数列
的前
项和
.
![](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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/141cf7ed7dd71ab172e9faa95919f9c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f30f56664446f32dbbc2c5f12a99374.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c9a601b25c9c9acae84b899c2690a31.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)
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名校
解题方法
5 . 已知正项等差数列
的前
项和为
,且
,
.则( )
![](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/3d93f25701735c01e7cec3ec62dcdf98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca8f4cea03f0098fdbce50b4d4b95ef7.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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2024-02-03更新
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1028次组卷
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10卷引用:【名校面对面】2022-2023学年高三大联考(5月) 理数试题
【名校面对面】2022-2023学年高三大联考(5月) 理数试题四川省内江市威远中学校2024届高三下期第一次月考理科数学试题理科数学-【名校面对面】2022-2023学年高三大联考(2月)试题文科数学-【名校面对面】2022-2023学年高三大联考(2月)试题四川省成都市第七中学2024届高三下学期入学考试数学(文)试题四川省成都市第七中学2023 2024学年高三下学期入学考试理科数学试卷四川省成都市第七中学2024届高三下学期开学考试数学(理)试题四川省内江市威远中学校2024届高三下学期第一次模拟考试文科数学试题(已下线)第四套 最新模拟重组卷山东省淄博市沂源县第二中学2023-2024学年高二下学期4月月考数学试题
解题方法
6 . 在前
项和为
的等差数列
中,
,
,则
( )
![](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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7a2b096d82bd60565d8d9478cec5523.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d648520b133ad41c505d5713cb656cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ebce85ea9bc18815ef8887057030a63.png)
A.5 | B.15 | C.45 | D.90 |
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2卷引用:【名校面对面】2022-2023学年高三大联考(11月)文数试题
7 . 已知等差数列
公差为2,且
,
,
恰为等比数列
的前三项.
(1)求数列
的通项公式;
(2)若数列
满足
,求
的前n项和
.
![](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/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/add46ec383fd80f41b3219a8e22c833b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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|
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4卷引用:天域全国名校协作体2023-2024学年高三上学期10月联考数学试题
天域全国名校协作体2023-2024学年高三上学期10月联考数学试题河北省石家庄市河北省实验中学2024届高三上学期名校联考数学试题(已下线)河北省石家庄市河北省实验中学2024届高三上学期名校联考数学试题变式题15-18(已下线)第05讲 4.3.2等比数列的前n项和公式(7类热点题型讲练)-【帮课堂】2023-2024学年高二数学同步学与练(人教A版2019选择性必修第二册)
名校
解题方法
8 . 在前
项和为
的等差数列
中,
,
,则
( )
![](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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb0ea3ca5891318d12aacd55c8e59cfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c12588db47476f2cf7e18b929ed9e39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614306cc3f34bdee4d5d885b79667645.png)
A.3 | B.10 | C.15 | D.25 |
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|
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5卷引用:【名校面对面】2022-2023学年高三大联考(11月)理数试题
解题方法
9 . 记Sn为等差数列{an}的前n项和.已知S4=0,a5=5,则( )
A.an=2n-5 | B.an=3n-10 |
C.Sn=2n2-8n | D.Sn=n2-4n |
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名校
解题方法
10 . 已知
是首项为19,公差为
的等差数列,
为
的前
项和.
(1)求通项
及
;
(2)设
是首项为1,公比为2的等比数列,求数列
的通项公式及其前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbd40e04e2a943051fa83d6e511add.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)求通项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79768a4e3970a18741cee3fbd8bcbdad.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)
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