名校
1 . 为了解某校高二学生的视力情况,随机地抽查了该校100名高三学生的视力情况,得到频率分布直方图如图,由于不慎将部分数据丢失,但知道前4组的频数成等比数列,后6组的频数成等差数列,设最大频率为
,视力在4.6到5.0之间的学生数为
,则
的值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/4/40c3e9b1-f7fd-4808-a816-b492a4220ecb.png?resizew=335)
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2 . 数列
中,
,
,则数列
的前62项之和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28e7e8fbb1fe7b910bbb25f2fd9a302a.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8838da7dd0d8b3055905a97e11db003.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d53b3d63b5cf8bd7c3105f50efab9953.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28e7e8fbb1fe7b910bbb25f2fd9a302a.png)
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3 . 西部某地区有沙地
亩,从
年开始每年在沙地植树造林,第一年年底共植树
亩,以后每一年年底比上一年年底多植树
亩.
(1)假设所植树苗全部成活,则到哪一年年底植树后可将沙地全部绿化?
(2)若每亩所植树苗木材量为
立方米,每年所值树木,从它种下的第二年起,木材量自然增长率为
,求沙地全部绿化后的那年年底该山林的木材总量 (精确到整数).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2a898ad48f314c02c5041a80ff0563e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6241896e3bb87fa99d76eb2674ce2256.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e6f1af4b44b2e97e8f319bab4ae9010.png)
(1)假设所植树苗全部成活,则到哪一年年底植树后可将沙地全部绿化?
(2)若每亩所植树苗木材量为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8ee628efd6b2f7296c106dd5cbae42f.png)
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解题方法
4 . 在等差数列
中,
,则其前n项和
最小时,n的值为_____________.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f849c711ca5d5bc67adb6545abb72886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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名校
解题方法
5 . 已知等差数列
的前和为
,若
,
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c57bbef89a37f1a3808c0ceeac0c22.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/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48c4dfd03461b477344781b866e3fdac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6858b87af2a83a7698a276772f6e7bfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c57bbef89a37f1a3808c0ceeac0c22.png)
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2021-11-23更新
|
696次组卷
|
2卷引用:上海市七宝中学2022届高三上学期期中数学试题
6 . 等差数列
的前n项和记为
,若
的值为一个确定的常数,则下列各数中也是常数的是( )
![](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/81665229041a0454237841d8e5976c8f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 将正整数数列
的各项按照上小下大的、左小右大的原则写成如下的三角形数表.数表中的第10行所有数字的和为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ca362fdc942383a853143b5c08f678.png)
![](https://img.xkw.com/dksih/QBM/2021/8/18/2788401689198592/2794752833953792/STEM/49f14f61213d4ad0a6485362fa3d386e.png?resizew=141)
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2021-08-26更新
|
580次组卷
|
4卷引用:上海市行知中学2021-2022学年高二上学期期中数学试题
上海市行知中学2021-2022学年高二上学期期中数学试题北京市海淀区北京理工大学附属中学2020-2021学年高二6月月考数学试题(已下线)期中模拟预测卷01(测试范围:空间向量与立体几何、数列) -2022-2023学年高二数学上学期期中期末考点大串讲(沪教版2020必修第三册+选修一)(已下线)4.1等差数列的前n项和(第2课时)(1)
名校
解题方法
8 . 已知等比数列
的公比
,
,且
、
、
成等差数列.
(1)求数列
的通项公式;
(2)设
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45482d31d1d7448c9f3922b4d2a55331.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a086dd951924fd2a094fc1d4da4341d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b2667a6c91b720ca9b42d092c776cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b6fae41755ecb64ac239a5a2d767354.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a1514ce14e8727ccf637b1a7776a347.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0f6000421c5370e4b89f23be199f388.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5ee9273cc82d57d99a21fb9c4953d46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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2021-07-19更新
|
1029次组卷
|
5卷引用:上海市实验学校2020-2021学年高一下学期期末数学试题
上海市实验学校2020-2021学年高一下学期期末数学试题(已下线)选择性必修第二册全册数学检测题(B卷综合篇)-2021-2022学年高二数学同步单元AB卷 (人教A版2019选择性必修第一册+第二册,浙江专用) (已下线)考点21 等比数列及其前n项和-备战2022年高考数学一轮复习考点帮(浙江专用)(已下线)2020年高考全国3数学文高考真题变式题16-20题辽宁省抚顺市抚顺县高级中学校2021-2022学年高二下学期3月月考数学试题
9 . 在公差不为零的等差数列
中,
是
与
的等比中项,则
=_____ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc858b7a95c5006a44067022da09f667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4299fa080986ce4682f8e626acc7390.png)
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解题方法
10 . 数列
是公差不为零的等差数列,其前
项和为
,若记数据
,
,…,
的方差为
,数据
,
,
,…,
的方差为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4694c10a53a0488f17a1c69ea7be73b9.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90707999e8fc89ae1137e5115c39f637.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ca64f1e0fd56584d82a4a298e0b8778.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06ce472cb48b49f019a7b3c1132e73e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fffe2c086360e30184b239b4463c7a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/436b003ca2ebe125b127418b41785e3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7338b951dcc7ce29f05971ada673727.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7345f310975ddb40dca94b5135c35dad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4694c10a53a0488f17a1c69ea7be73b9.png)
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