1 . 设等差数列
的公差为
,记
是数列
的前
项和,若
,
.
(1)求数列
的通项公式;
(2)若
,数列
的前
项和为
,求证:
.
![](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/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/9640394bcbf52c435bdfa5e108002e4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1959cec7b14403c2b839111c5e15bdb1.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/065b4c79e7a73cc0b1a2d444e0cf13f0.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/62c630ae094545da6da659feb70ef0ca.png)
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2024-04-12更新
|
1968次组卷
|
3卷引用:2024届浙江省丽水、湖州、衢州三地市二模数学试卷
名校
解题方法
2 . 已知等差数列
的前n项和为
,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf14ebc775db2414a5a960badca8960.png)
_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af0a8e313d86fb85b3666b2b6b554efa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf14ebc775db2414a5a960badca8960.png)
您最近一年使用:0次
2024-03-03更新
|
610次组卷
|
2卷引用:浙江省丽水市2023-2024学年高二上学期1月期末教学质量监控数学试题
名校
3 . 设等差数列
的前n项和为
,满足
,
,则( )
![](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/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59f1422fabf3143a5ab312794c420b5f.png)
A.![]() | B.![]() ![]() |
C.![]() | D.满足![]() |
您最近一年使用:0次
2020-06-03更新
|
898次组卷
|
4卷引用:浙江省丽水市发展共同体2019-2020学年高一下学期期中数学试题
浙江省丽水市发展共同体2019-2020学年高一下学期期中数学试题四川省射洪中学校2019-2020学年高一下学期期中考试数学试题(已下线)卷18-【赢在高考·黄金20卷】备战2021高考数学全真模拟卷(北京专用)四川省眉山市仁寿第一中学校南校区2023-2024学年高二下学期3月月考数学试题
4 . 等差数列
中,
,且
,
,
成等比数列.
(1)求数列
的通项公式;
(2)记
为数列
的前
项和,是否存在正整数
,使得
?若存在,求出
的最小值;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/86fc336b4a83bf6d66c4afcc431597f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fd71bc7e6668f90f259ad0b06dd60c2.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记
![](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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25be6d08e05c159ccdf583259d113925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
5 . 已知在等差数列
中,若
,则前
项和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
__________ ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/767c9f886e5b58c437f39f841872b300.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7033a80ada728281eb4629a84c38cc3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d02ea8c4988c5c28ab93f0d70fb55a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/767c9f886e5b58c437f39f841872b300.png)
您最近一年使用:0次
2016-12-04更新
|
375次组卷
|
4卷引用:浙江省丽水外国语实验学校2019-2020学年高一下学期期初数学试题