名校
解题方法
1 . 已知等差数列
的前n项和为
,
,
,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/e158513b2c3029627d22ca1caf0969bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e658702682b46502299203c511396f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5af1f1b7e9e20d799ee3c06b89a0611c.png)
A.55 | B.60 | C.65 | D.75 |
您最近一年使用:0次
2022-12-16更新
|
788次组卷
|
6卷引用:四川省绵阳市开元中学2021-2022年学年高一下学期期末适应性质量检测理科数学试题
四川省绵阳市开元中学2021-2022年学年高一下学期期末适应性质量检测理科数学试题四川省绵阳市开元中学2021-2022年学年高一下学期期末适应性质量检测文科数学试题天津市耀华中学2022-2023学年高二上学期期末数学试题(已下线)1.2.2等差数列的前n项和同步课时训练-2022-2023学年高二下学期数学北师大版(2019)选择性必修第二册江苏省南京市第九中学2023-2024学年高二上学期10月阶段学情调研数学试题江苏省苏州市三校2023-2024学年高二上学期10月阶段检测数学试题
2 . 已知数列
中,
,
.
(1)求数列
的通项公式;
(2)若数列
前n项和
,求n的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53f63b9a97402af3d61fadb37a283e6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2bdd4f0177a7757465ac361a63838b4.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67be3e8aeb202b671a15bdba1952b6d9.png)
您最近一年使用:0次
2022-12-16更新
|
474次组卷
|
3卷引用:四川省绵阳市开元中学2021-2022年学年高一下学期期末适应性质量检测理科数学试题
解题方法
3 . 已知数列
的前
项和
(其中
为常数,
),写出使
不为等差数列的一个通项公式![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.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/7951aab86922f0c881b27f3902e61768.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3692d8fc8e9408781ca472eba17709f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
您最近一年使用:0次
4 . 2022北京冬奥会开幕式将我国二十四节气融入倒计时,尽显中国人之浪漫,倒计时依次为:大寒、小寒、冬至、大雪、小雪、立冬、霜降、寒露、秋分、白露、处暑、立秋、大暑、小暑、夏至、芒种、小满、立夏、谷雨、清明、春分、惊蛰、雨水、立春,已知从冬至到夏至的日影长等量减少,若冬至、小雪、霜降三个节气的日影长之和为34.5寸,冬至到秋分等七个节气的日影长之和为73.5寸,问立秋的日影长为( )
A.1.5寸 | B.2.5寸 | C.3.5寸 | D.4.5寸 |
您最近一年使用:0次
名校
解题方法
5 . 已知等差数列
中,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31ac44bbb551bede8ea218254a4c1c87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a7bf78468ca801ef305ce4f76986da1.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2022-07-21更新
|
651次组卷
|
3卷引用:四川省遂宁市遂宁中学校2021-2022学年高一下学期期末数学试题
6 . 已知数列
满足
,
.
(1)求证:数列
为等差数列;
(2)求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e89bddd9c021a9caccc72cd0189e1ceb.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a44cfbb86a4eb76261c00ddc6bff181.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b040fc89872638210abc01b011d6018c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
名校
解题方法
7 . 已知等差数列
满足
,
.
(1)求数列
的通项公式;
(2)求数列
的前n项和
.
![](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/db0ac8195213e38a99caacd83db157b7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d86b57ce3be486d3d8cddcc5b1cba238.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
2022-07-21更新
|
921次组卷
|
4卷引用:四川省凉山彝族自治州2021-2022学年高一下学期期末数学(理)试题
解题方法
8 . 已知等差数列
中,
,
,则该数列前6项的和为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2815b24f5a89be7ae53aed93182e8988.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/917b229d7588aa46a4f1a724132d1c07.png)
您最近一年使用:0次
名校
9 . 我国古代数学著作《周髀算经》中记载了二十四节气与晷长的关系:每个节气的晷长损益相同.晷是按照日影测定时刻的仪器,晷长即为所测量影子的长度,如图1所示,损益相同,即相邻两个节气晷长减少或增加的量相同,且周而复始.二十四节气及晷长变化如图2所示.已知谷雨时节晷长为5.5尺,霜降时节晷长为9.5尺,则二十四节气中晷长的最大值为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/30/7ce430de-ac85-4ff1-bdef-cf37a102a85f.png?resizew=215)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/30/337517e3-8904-467e-a5f1-3b34bb79129d.png?resizew=189)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/30/7ce430de-ac85-4ff1-bdef-cf37a102a85f.png?resizew=215)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/30/337517e3-8904-467e-a5f1-3b34bb79129d.png?resizew=189)
A.14.5 | B.13.5 | C.12.5 | D.11.5 |
您最近一年使用:0次
2022-07-17更新
|
503次组卷
|
4卷引用:四川省成都市双流区2021-2022学年高一下学期期末数学试题
解题方法
10 . 已知正项数列
的前
项和为
,
,且
.
(1)求数列
的通项公式;
(2)若
,求数列
的前n项和
.
![](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/bc551a847928aca93e25096b335e9676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41be41a5a4965ebd346e7ee74d21f0f3.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/216876de04325fd250c38c485cbc34b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
2022-07-15更新
|
395次组卷
|
2卷引用:四川省成都市2021-2022学年高一下学期期末数学(文科)试题