1 . 若
分别是正数
的算术平均数和几何平均数,且
这三个数可适当排序后成等差数列,也可适当排序后成等比数列,则
的值是_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f7058ee90c9d1bd2b50fb4b4c0b8427.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddbf8c44767de923de09a6aa6c5fda35.png)
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2 . 已知
为等差数列
的前
项和,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5af1f1b7e9e20d799ee3c06b89a0611c.png)
___________ .
![](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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/164afbf55ea7cd7d66158620616e604e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5af1f1b7e9e20d799ee3c06b89a0611c.png)
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2021-10-22更新
|
645次组卷
|
2卷引用:四川省成都石室中学2021-2022学年高三上学期10月月考数学(文)试题
名校
解题方法
3 . 在
中,内角
,
,
的对边分别为
,
,
,若
,
,
成等差数列,
,且
,则
的面积为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](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/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65e3b67bbfe99101796d2f16fbe01a80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e258ab9e600435b37465092243d99f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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2021-10-21更新
|
1003次组卷
|
6卷引用:河南省大联考2021-2022学年上学期高中毕业班阶段性测试(二)理科数学试题
4 . 已知等差数列
和
的前
项和分别为
和
,且有
,
,则
的值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/495a9d24dcf6d308d48b0d55f4ce7880.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/532d7c5de4522ac5d4d767ccb28b352a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe14b5f2c6324410e403c91512f7d9e.png)
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2021-08-27更新
|
1301次组卷
|
4卷引用:贵州省贵阳市五校(贵州省实验中学、贵阳二中、贵阳八中、贵阳九中、贵阳民中)2022届高三联合考试(一)数学(理)试题
贵州省贵阳市五校(贵州省实验中学、贵阳二中、贵阳八中、贵阳九中、贵阳民中)2022届高三联合考试(一)数学(理)试题贵州省贵阳市五校(贵州省实验中学、贵阳二中、贵阳八中、贵阳九中、贵阳民中)2022届高三联合考试(一)数学(文)试题(已下线)专题11 有关等差(比)数列的基本运算——备战2022年高考数学二轮复习常考点专题突破(已下线)4.1 等差数列(精练)-【一隅三反】2023年高考数学一轮复习(基础版)(新高考地区专用)
20-21高三下·全国·阶段练习
5 . 已知在等比数列
中,
且
成等差数列﹐则
的通项公式![](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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9396a4a1a1f97519f872cf1e6ad1322f.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
6 . 在一个有限数列的每相邻两项之间插入这两项的等差中项,从而形成一个新的数列,我们把这样的操作称为该数列的一次扩充.如数列
,
,扩充一次后得到
,
,
,扩充两次后得到
,
,
,
,
,以此类推.设数列
,
,
(
为常数),扩充
次后所得所有项的和记为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c2864e2ec3416cc4c081ac1f71a0af.png)
______________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d02ea8c4988c5c28ab93f0d70fb55a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d91e07104b699c4012be2d26160976a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d02ea8c4988c5c28ab93f0d70fb55a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d91e07104b699c4012be2d26160976a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b06e95b57b7a81cd81d05557a11fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d02ea8c4988c5c28ab93f0d70fb55a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.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/04c2864e2ec3416cc4c081ac1f71a0af.png)
您最近一年使用:0次
2021-04-16更新
|
581次组卷
|
5卷引用:河南省名校联盟2020-2021学年高三4月联考(一)理科数学试题
河南省名校联盟2020-2021学年高三4月联考(一)理科数学试题(已下线)押第15题 数列-备战2021年高考数学(理)临考题号押题(全国卷1)内蒙古自治区通辽新城第一中学2021届高三第三次增分训练数学(理)试题(已下线)押新高考第14题 数列-备战2021年高考数学临考题号押题(新高考专用)人教A版(2019) 选修第二册 突围者 第四章 章末培优专练
7 . 已知等比数列
中,
,
,
,
成等差数列.则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6284b6773305e1d774156305da88b96c.png)
___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9645bd4d2002993b90ec6d48f9c04f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a37f1b45e929b42044626edb63681fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20071a42c1f9eac2b173d77d37381da9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/911278aa8595846abac1972e1de59995.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6284b6773305e1d774156305da88b96c.png)
您最近一年使用:0次
8 . 已知数列
为等比数列,数列
为等差数列,若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb9bd3f05d0b3341b5ffd7d9acb7ea61.png)
________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fc9b87a80a62b2d19281e0e66994528.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdb4d1349bcdd0c8cc969b4108dd3f5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb9bd3f05d0b3341b5ffd7d9acb7ea61.png)
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2021-03-24更新
|
209次组卷
|
2卷引用:重庆市巴蜀中学2021届高考适应性月考卷(八)数学试题
名校
解题方法
9 . 已知正项数列
中,
,
,
,
,数列
的前n项和为
,则
的值是________ .
![](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/9c9b6e51986fe5d7a7265e0e93adcb4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84ab91bd407f2d31e75ccdc0722d27cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3c4372fd35348f5c79c2f07f27cc2a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fddf1ad033756db46a40f2c750f6fbfc.png)
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2021-03-22更新
|
248次组卷
|
2卷引用:四川省遂宁市大英县大英中学2022-2023学年高三下学期3月月考数学试题
20-21高二·全国·课后作业
名校
10 . 等差数列
中,若
,
为方程
的两根,则
等于__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1a50f815f27b1c935fe28935cb2d3ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02bc85419a13c4edb085384e84bcb556.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20cb592e7545ac9e1d78965d57dbd0a5.png)
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2021-03-10更新
|
1036次组卷
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5卷引用:新疆维吾尔自治区喀什第六中学2023届高三上学期9月实用性月考(一)数学(文)试题
新疆维吾尔自治区喀什第六中学2023届高三上学期9月实用性月考(一)数学(文)试题新疆维吾尔自治区喀什第六中学2023届高三上学期9月实用性月考(一)数学(理)试题内蒙古阿拉善盟2023届高三第一次模拟考试数学(文)试题(已下线)4.2.1 等差数列的概念(2)B提高练(已下线)专题02 等差数列和等比数列的性质-2020-2021学年高二数学数列专题复习课(人教A版2019选择性必修第二册)