名校
解题方法
1 . 等差数列
中,设
为其前
项和,且
,
,则当
为______ 时,
最大.
![](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/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39d276841f55daf6114bdf34e39b9907.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
解题方法
2 . 等差数列
中,
为其前
项和,且
,则
最大时
的值为( )
![](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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e0cea429112f55c8321c74f545a3e3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
A.7 | B.10 | C.13 | D.20 |
您最近一年使用:0次
2020-05-26更新
|
605次组卷
|
3卷引用:山西省忻州实验中学2019-2020学年高二下学期第一次月考数学试题
山西省忻州实验中学2019-2020学年高二下学期第一次月考数学试题云南省曲靖市沾益区第四中学2020-2021学年高二5月月考数学(理)试题(已下线)专题02 等差数列及前n项和(专题测试)-2020-2021学年高二数学重难点手册(数列篇,人教A版2019选择性必修第二册)
名校
解题方法
3 . 若等差数列
的首项
,
是其前
项和,
,
,则使
成立的最大正整数
是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390636a89883bd64bf8da9bf8654aff9.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/9ba7610f08d3da90ec366313f6c2fc6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43ef4ed6f04cf3f21a5b52aea11ae80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49763402b2f2023f0ba64c37924267d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
2020-05-25更新
|
442次组卷
|
3卷引用:2020届安徽省皖江名校联盟高三下学期5月联考数学(理)试题
名校
解题方法
4 . 已知等差数列
的前
项和为
,且
,
,则使得
取最小值时的
为( )
![](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/25fc75492746a0a80051c0d6ae885b7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6be502c25f102f0d8092c8ad906da02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
A.9 | B.7 | C.6 | D.6或7 |
您最近一年使用:0次
解题方法
5 . 已知等差数列
的前
项和为
,
,
,则使得
达到最大值的
是________ .
![](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/12e7bae8e3bfecaceda505bb320563e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2eef5fd54a3cc52795078cfb9eb353e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
名校
解题方法
6 . 记
为等差数列
的前
项和,若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd5ce002f88a27b0b151f5122c4cae26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
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2020-04-27更新
|
601次组卷
|
3卷引用:湖北省孝感市应城市第一高级中学2019-2020学年高二下学期期中数学试题
名校
解题方法
7 . 已知{an}为等差数列,a1+a2+a3=165,a2+a3+a4=156,{an}的前n项和为Sn,则使得Sn达到最大值时,n=( )
A.19 | B.20 | C.21 | D.22 |
您最近一年使用:0次
2020-03-22更新
|
295次组卷
|
4卷引用:湖北省襄阳市第四中学2019-2020学年高三上学期9月联考数学(文)试题
8 .
是等差数列
的前
项和,若
,
,则使得
取得最大值的
( )
![](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/a81974dea9c97235cfeba7551bc0e696.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c864fb2f798930481536e52374adc6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
A.8 | B.7 | C.9 | D.10 |
您最近一年使用:0次
名校
9 . 设等差数列
前n项和为
.若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
________ ,
的最大值为________ .
![](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/9652f65b28e2032c0cbc2a9649db4f51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36989853e0d247e504b292e17d8a8cfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
2020-02-20更新
|
636次组卷
|
8卷引用:2020届山东师范大学附属中学高三第三次月考数学试题
2020届山东师范大学附属中学高三第三次月考数学试题(已下线)第02章等差数列(A卷基础卷)-2020-2021学年高二数学必修五同步单元AB卷(苏教版,新课改地区专用)(已下线)考点18 等差数列与等比数列的基本量-2021年高考数学三年真题与两年模拟考点分类解读(新高考地区专用)(已下线)专题4.2 数列的通项与求和-备战2021年高考数学精选考点专项突破题集(新高考地区)(已下线)考点40 数列的概念与等差数列-备战2022年高考数学一轮复习考点帮(新高考地区专用)【学科网名师堂】(已下线)第4章 等差数列(A卷·夯实基础)-2021-2022学年高二数学同步单元AB卷(苏教版2019选择性必修第一册)【学科网名师堂】北京市第二中学2021-2022学年高二下学期数学期末练习试题(已下线)第43讲 数列的求和
名校
10 . 已知
为等差数列,
为其前
项和.若
,
,则公差
_____ ;
的最小值为_____ .
![](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/a51c55e7bfb89ad0113afaf43834438c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fcf7a9495359d1beedf9a6a1f07e7f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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