1 . 已知等差数列
的公差
,
与
的等差中项为5,且
.
(1)求数列
的通项公式;
(2)设
求数列
的前20项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ce64685821c3e55c07f151996ca8c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7da2f386b78cdf6489efaa2f5820d3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78d4d35ddfc27da37f4fa38ee424e508.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6907d5edb3b722809ce1d6ec272847d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2f710b0e6ccca316852bf3a94f68135.png)
您最近一年使用:0次
昨日更新
|
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3卷引用:黑龙江省双鸭山市第一中学等校2024届高三第四次模拟数学试题
黑龙江省双鸭山市第一中学等校2024届高三第四次模拟数学试题广东省江门市开平市开侨中学2023-2024学年高二下学期期末热身模拟数学试题(已下线)高二数学下学期期末考点大通关真题必刷100题(2) --高二期末考点大串讲(人教B版2019选择性必修第二册)
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2 . 已知
为等差数列
的前n项和,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a59b6d44509728b04821c38e4f0771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9334dc3344670bf8962c98f7893a969e.png)
A.4 | B.6 | C.8 | D.10 |
您最近一年使用:0次
3 . 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/72d0dc3181f37d7da2b3809da52f4769.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d36243198e5e20c56399e4ad5ac3c519.png)
A.9 | B.12 | C.18 | D.24 |
您最近一年使用:0次
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4 . 设某直角三角形的三个内角的余弦值成等差数列,则最小内角的正切值为__________ .
您最近一年使用:0次
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5 . 已知等差数列
的前
项和为
,
,
,则
( )
![](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/5170584604571b5e1afd5ece941e2e73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3b75ec86aa0e1fe86f6fdeee4ab26ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eab8f8926b996f9bee57d96067f5bac.png)
A.18 | B.21 | C.24 | D.27 |
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2024-06-13更新
|
192次组卷
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2卷引用:2024届山东省五莲县第一中学高三模拟预测数学试题
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解题方法
6 . 已知数列
为各项均不相等的等比数列,其前
项和为
,且
成等差数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbe0fb36fe99ec888b46996e4826291a.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/4e7f999ebf988f082bfe6a77401e19b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbe0fb36fe99ec888b46996e4826291a.png)
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7 . 在
中, 角
所对的边分别为
, 若
成等差数列, 则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c5688323a324c9b1d08a9b43355f41f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
解题方法
8 . 已知等比数列
的公比不为1,若
,且
成等差数列,则
( )
![](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/90b5b91367b7cbf08768c6a9274898d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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9 . 在等差数列
中,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77dc2f6f53df3eeda1fb1dd6b0bac8ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0382b4a2ab0657d2d6830bb6be2b17b6.png)
A.21 | B.24 | C.27 | D.29 |
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2024-05-31更新
|
577次组卷
|
2卷引用:四川省雅安市2023-2024学年高三三诊数学(理)试题
10 . 已知关于
的方程
的所有正实根从小到大排列构成等差数列, 请写出实数
的一个取值为______
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20497296b080f45a2eb51b7ce88d0407.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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