1 . 在①
,
,
成等比数列,②
,③数列
的前10项和为55.这三个条件中任选一个,补充在下面问题中,并解答问题.
已知等差数列
的前
项和为
,公差
,且__________
(1)求数列
的通项公式;
(2)求数列
的前2023项和.注:如果选择多个条件分别解答,按第一个解答计分.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/359ee9d15f5390bdb02c62855451323c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afca2a021efa9ec2ff31388c198119db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dea1dd4ffcb4cf0697ca43079f6a1f2.png)
已知等差数列
![](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/c5c1344592c925b273f2cb9b9e47ebbb.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/ba57c83d526ac308d1461e80fcca9f36.png)
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名校
解题方法
2 . 各项不为0的数列
满足
,且
.
(1)求证:数列
为等差数列;
(2)若
对任意
恒成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea57eca4b72f73d23c3fed1bc61b414a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/562bf10d55724c77204c6953c7fbf7e2.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41cf1da18d91f7c98086553d157d1a87.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8355941ad1ce719c3164c1c39bd5b448.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
2023-03-03更新
|
1658次组卷
|
5卷引用:湖南省湘西州吉首市2023年第二届中小学生教师解题大赛数学试题
3 . 已知各项均为整数的等差数列
,若
,
,
,则
的最小值是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/086f7627ecc5df5a2ab07201b8732fd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46efbcdf49c567b8cd9e1bbaa14ee365.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bcd8a9ba1cf84f417fb9055b7c3737e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae9dd56551121a5b88be4dc6910c9ec0.png)
您最近一年使用:0次
4 . 已知集合
,设
是等差数列
的前
项和,若
的任意一项
,且首项
是
中的最大值,
.
(1)求数列
的通项公式;
(2)若数列
满足
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a101d7fe85109e613e4fdff218e32f5.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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6302fc3e3d1fac960e84950c0e814a19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fdbfa7a63fdf5717d40c8c9a73ec160.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b18378ba893f1ce0814c9582699ae29.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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/166e346727bcaf56431b36ef42594af6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b511d10eb2d2d913d7282778206db331.png)
您最近一年使用:0次
解题方法
5 . 对于数列
,定义
为
的“优值”,已知某数列
的“优值”为
,记数列
的前n项和为
,若
对任意的n恒成立,则实数k的取值范围为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/970b408e394a469cf86916e899e1ed80.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/d935e25db28c6ec9b7ae700cd335edbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071c744a45fd2d97a3e616a04495ff6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3523a941f4af78066c6f587e8d001df0.png)
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6 . 等差数列
中,
,则数列
的公差![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67eaaaaee28891b63123ef9e5c6444c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
您最近一年使用:0次
名校
解题方法
7 . 已知正项数列
的前n项和为
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f5eb9b8f893dd71876349ad40724550.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/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec1e07c5b19e513d4155be61cd7e6798.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f5eb9b8f893dd71876349ad40724550.png)
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解题方法
8 . 已知正项数列
满足
,
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679401be6da078a518f95f9211dff17b.png)
__________ .
![](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/f966272f7781790ff27e40db6b525253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b761d6268e67b2b64c3c299b58cd42fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679401be6da078a518f95f9211dff17b.png)
您最近一年使用:0次
9 . 已知数列
的前
项和为
,
,当
时,
,则
等于( ).
![](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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5c7aea03e32b2a79d5a84276192ee12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dbaa389d7a95763ccd960130e7e70e7.png)
A.1008 | B.1009 | C.2016 | D.2017 |
您最近一年使用:0次
解题方法
10 . 已知数列
的前
项和为
,等比数列
的首项
,公比为
.
(1)求两数列
的通项公式
;
(2)设
,若存在
,使得
成立,求数列
的和.
![](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/3752a6f0cf0024457b506c2c4b6a50e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eba7bb60b94d0b62978c92989420a54a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
(1)求两数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0914c295f572c98dd043d4f84268934.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/626d82c9a1e2b37c41ea6e73ba0a1f77.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36407bc32faaa0d26aabe0734fcd437c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7905fd422e78a1d22ff6f11950bc5cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e31585a72bee2854c2595573fc9db1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acab2a43d2177985b5247dc2f96dfb46.png)
您最近一年使用:0次