1 . 已知数列
满足
,则数列
的前
项和的最大值是__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f8b931bae0fdf8f77c6b19049e36cfa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bf3da897eb73b729f66bb0d700775c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
解题方法
2 . 已知等差数列
的前
项和为
,若
,则当
最小时,
的值为__________ .
![](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/1ada98fc376ae818d1d73452500f4158.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
3 . 在数列
中,
,
,则当n=________ 时,前n项和
取最大值,最大值是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a086dd951924fd2a094fc1d4da4341d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b299ab58ca8675426604c3e634ab1b79.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
4 . 数列
中,
,当数列
的前n项和
取得最小值时,n=________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/709bd1e26941edd5b56438a1325a3fc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
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解题方法
5 . 设等差数列
的前
项和为
,则有以下四个结论:
①若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99ca47be5a21ea60ebd04dd8945852d8.png)
②若
,且
,则
且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eef1f2c439ad1043f4b0e8892066826.png)
③若
,且在前16项中,偶数项的和与奇数项的和之比为3:1,则公差为2
④若
,且
,则
和
均是
的最大值
其中正确命题的序号为___________ .
![](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)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd67cf18bd35149475d35f1c603ad59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99ca47be5a21ea60ebd04dd8945852d8.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c45c65fa15317b33766389407c427668.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/642a443e3315a7fb6489b01fad7e3215.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd3c579e5e0540f190994cbb5b0653a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eef1f2c439ad1043f4b0e8892066826.png)
③若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b8bdb404dcbe74cd8bbd30de782a8fa.png)
④若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8933c07e3651731291184c080766c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41c4154f019120be078200f2dff6f4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f30f56664446f32dbbc2c5f12a99374.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
其中正确命题的序号为
您最近一年使用:0次
2023-11-26更新
|
503次组卷
|
5卷引用:4.2.2 等差数列的前n项和公式——课后作业(提升版)
(已下线)4.2.2 等差数列的前n项和公式——课后作业(提升版)宁夏银川市唐徕中学2023-2024学年高三上学期期中考试数学(理)试题北京朝阳区六校联考2024届高三12月阶段性诊断数学试题北京第五中学2023-2024学年高三下学期开学检测数学试卷(已下线)2024年高考数学二轮复习测试卷(北京专用)
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解题方法
6 . 设等差数列
的前n项和为
,公差
,
,则当
取最小值时,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
______ .
![](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/c4ce64685821c3e55c07f151996ca8c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcbc4b5f4552cde04ac3e73f1bde84a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
您最近一年使用:0次
2023-10-07更新
|
839次组卷
|
5卷引用:4.2.2 等差数列的前n项和公式——课后作业(提升版)
(已下线)4.2.2 等差数列的前n项和公式——课后作业(提升版)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江苏省淮安市楚州中学、新马中学2024届高三上学期第二次阶段检测数学试题(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11-14
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解题方法
7 . 已知等差数列
的前n项和为
,
,
,则
取得最大值时n的值为__________ .
![](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/1b59a6850258e6025e6c155808b7c1fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f36463fd0688d3ed167f91a35c6cd18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
解题方法
8 . 等差数列
中,
是它的前n项的和,且满足
.则
的最大值为__________ ;数列
的前n项和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7978d7bd6f6caf9ac9837ffce5f89654.png)
__________ .
![](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/5bfbd4d39063d5f444eb93c7cbbc4b64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b91adba8efbf964e9e35547b0fd0ea36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7978d7bd6f6caf9ac9837ffce5f89654.png)
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22-23高二下·全国·课后作业
9 . 在等差数列
中,
,则
取最大值时n的值是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7261c144b4247e997b7c0f8afb60a9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
名校
10 . 已知等差数列
的前
项和为
,若
,公差
,当且仅当
时,
取得最大值,则
的取值范围是__________ .
![](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/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2d8bbb4a09e0ac86bbae46222a90841.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08ec5d76db9bd05547932966c9913dc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/692d2d3244696e8f76a66a048df4d834.png)
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