名校
解题方法
1 . 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
|
505次组卷
|
5卷引用: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
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)(已下线)4.2.2 等差数列的前n项和公式——课后作业(提升版)
2 . 定义:数列
对一切正整数
均满足
,称数列
为“凸数列”,以下关于“凸数列”的说法:
①等差数列
一定是凸数列;
②首项
,公比
且
的等比数列
一定是凸数列;
③若数列
为凸数列,则数列
是单调递增数列;
④若数列
为凸数列,则下标成等差数列的项构成的子数列也为凸数列.
其中正确说法的序号是_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e772be971634dc7230df59d91399dc59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
①等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
②首项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f71acdb04454c77e1e25ad4f336cccfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45482d31d1d7448c9f3922b4d2a55331.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
③若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d82c65a855b1eed9c43e6829f6c3bffb.png)
④若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
其中正确说法的序号是
您最近一年使用:0次