名校
1 . 等差数列
满足:
,
.记
,当数列
的前
项和
取最大值时,![](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/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2f6bb3a65154ed4be7772de771ce8df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e8ac942d29135cb8f133cab143af1a0.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
A.17 | B.18 | C.19 | D.20 |
您最近一年使用:0次
2020-02-01更新
|
1155次组卷
|
6卷引用:安徽省安庆市第一中学2022-2023学年高二下学期第一次月考数学试题
名校
2 . 已知数列{
}的前n和
,且
,则
的最大值为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cef9a8407029d3109a91dda8edfcca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22d137eb2027f035fa1a36cfcec0626c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
您最近一年使用:0次
名校
解题方法
3 . 已知各项都是正数的数列
的前
项和为
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
(1)求数列
的通项公式;
(2)设数列
满足:
,
,数列
的前
项和
,求证:
;
(3)若
对任意
恒成立,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.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/a3676c51d6987107ebd4aadbffd82abc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65e7106269ab9893d2f9e132b7e54df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1a208706fe64c4a6709e9de5da2bdd.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/9c3fec47d2dd2b8099d86c87b6e57de8.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3f43b451711e573a9ea7ffcbbab3018.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
2020-10-12更新
|
512次组卷
|
10卷引用:【全国百强校】安徽省安庆市第一中学2018-2019学年高一下学期期中考试数学试题
【全国百强校】安徽省安庆市第一中学2018-2019学年高一下学期期中考试数学试题2015-2016学年黑龙江省哈尔滨六中高一下期中数学试卷2017届天津市六校高三理上学期期中联考数学试卷【区级联考】广东省深圳市宝安区2018-2019学年高二第一学期期末调研理科数学试题广东省深圳市宝安区2018-2019学年第一学期高二文科数学期末调研试题江苏省泰州市泰兴市黄桥中学2019-2020学年高二上学期11月月考数学试题江苏省徐州市侯集高级中学2019-2020学年高二上学期期末数学试题江苏省扬州市江都区大桥高级中学2020-2021学年高二上学期学情调研(一)数学试题江苏省盐城市响水中学2022届高三下学期3月学情分析(二)数学试题(已下线)山东省日照市2023届高三一模考试数学试题变式题17-22
解题方法
4 . 已知数列
的各项均为正整数,
.
(1)若数列
是等差数列,且
,求数列
的前n项和
;
(2)若对任意的
,都有
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c0ce0308f3de40fcf641d467c3224da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba57c83d526ac308d1461e80fcca9f36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)若对任意的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0b0b716fda9b1efd9e47e2d80543f2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02ce9d5623b21817dd182b9058dc271a.png)
您最近一年使用:0次
5 . 已知等差数列
的前n项和
满足
,
.
(1)求
的通项公式;
(2)若数列
的前n项和为
.证明:
.
![](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/4e1c1cf53ef58604978dc71b9846ad46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da7f12002611781ce9601baca8ae7ce3.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cfb8091a44e1edbc4dc5274a57cbd0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b0dcd26b203cbac098ea9a6824f163b.png)
您最近一年使用:0次
名校
6 . 已知从1开始的连续奇数蛇形排列形成宝塔形数表,第一行为1,第二行为3,5,第三行为7,9,11,第四行为13,15,17,19,如图所示,在宝塔形数表中位于第
行,第
列的数记为
,比如
,
,
,若
,则
( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/20/ffa4a20c-d6eb-4732-9cb1-fb295d309078.png?resizew=143)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7600d2cfbdc6146db96cc545706004f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4ba1bbe411bc71bca016d3fd82352f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fbb7397f2a4e7afb7361a13d7b95b5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea718cdbe681628efe6fa588cdb03ece.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923414bc484033641cdc7266e0499db3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af8cf0265b84100cb03246fcddae324f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4a0ffd97e63546f5181037e416a46aa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/20/ffa4a20c-d6eb-4732-9cb1-fb295d309078.png?resizew=143)
A.64 | B.65 | C.71 | D.72 |
您最近一年使用:0次
2019-12-27更新
|
559次组卷
|
4卷引用:安徽省安庆市怀宁县第二中学2018-2019学年高三上学期第四次月考数学(理)试题
安徽省安庆市怀宁县第二中学2018-2019学年高三上学期第四次月考数学(理)试题广东省汕头市金山中学2018-2019学年高三上学期期末数学(理)试题(已下线)专题12.1 合情推理与演绎推理 (精练)-2021届高考数学(文)一轮复习学与练(已下线)第二章 推理与证明(能力提升)-2020-2021学年高二数学单元测试定心卷(人教版选修2-2)
7 . 已知数列
中,
,前
项的和为
,且满足数列
是公差为1的等差数列.
(1)求数列
的通项公式;
(2)若数列
的前
项的和为
,且
恒成立,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.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/6a31c33279d82bc509aa921e2b0c03da.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若数列
![](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/3281381305100246444883dc93a2eef8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
8 . 已知公差为正数的等差数列
,
,且
成等比数列.
(1)求
;
(2)若
,求数列
的前
项的和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29b1b845916a4b6a18cdfbcd308d09c4.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/288d4efab50964b9b9d5fba3f1d22fc0.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)
您最近一年使用:0次
解题方法
9 . 设等差数列
的公差为d,若
,且
,则
的前n项和
取得最大值时项数n的值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9a12a33f60503feedbdcc15e972eec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4298e0cd3eff408efe49e364725692df.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
名校
10 . 已知数列
满足
是数列
的前
项的和.
(1)求数列
的通项公式;
(2)若
成等差数列,
,18,
成等比数列,求正整数
的值;
(3)是否存在
,使得
为数列
中的项?若存在,求出所有满足条件的
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97efa936324e9d010f2c69b1e6cd5a1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e58cc4080c55763043a54e3ee4b381f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb0f275144e42185c9c39a84e295de80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cda7c627d90efa5e1cdfcc6b05e1333d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3f87fbbd5c55339ec9601ce6772ebea.png)
(3)是否存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d629820038b0e73645e9ef45679a29e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdea605bef0ac4009fac8f037a71daeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
2018-07-27更新
|
599次组卷
|
4卷引用:【校级联考】安徽省示范高中培优联盟2018-2019学年高一下学期春季联赛数学(理)试题
【校级联考】安徽省示范高中培优联盟2018-2019学年高一下学期春季联赛数学(理)试题江苏省无锡市2018届高三第一学期期末检测数学试卷(已下线)专题20 与数列有关的恒成立问题-2018年高考数学(理)母题题源系列(江苏专版)江西省景德镇市景德镇一中2019-2020学年高二上学期期中数学(理)试题