1 . 已知数列
,则
是这个数列的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdeccac0b2635a23f63879e8c0d2d8e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b91d650c2fc1a741fabdb333b09aeb6.png)
A.第6项 | B.第7项 | C.第9项 | D.第11项 |
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2 . 已知数列
的前n项和为
,
,
.
(1)求数列
的前n项和
;
(2)令
,求数列
的前n项和
.
![](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/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93d163749744286a4d4425cf62071855.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7d3d55a85012933f91c5d8d27d8801d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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3 . 已知等差数列
满足
,
.
(1)求
;
(2)数列
满足
,
为数列
的前
项和,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a38c5d56a437f36bde9ce723233e0063.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f0c70e6e444d93f3afe408731b915e7.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5d40381d3b27fa12b06ee78494e0ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.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/fbd85b79372dc6e596d465f738c3c300.png)
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4卷引用:湖南省株洲市第一中学2022届高三上学期期末数学测试卷
湖南省株洲市第一中学2022届高三上学期期末数学测试卷广东省深圳市2023届高三冲刺(三)数学试题海南省儋州市洋浦中学2024届高三上学期11月月考数学试题(已下线)第02讲 等差数列及其前n项和(十大题型)(讲义)-2
4 . 公差为
的等差数列
的首项为
,前
项和为
,且满足
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.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/c49fcf2f7465fb869ca880a811634c46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/554e6c461ccc5aa3093c524aa528a4e2.png)
A.55 | B.60 | C.65 | D.70 |
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解题方法
5 . 已知等差数列
的公差不为零,
,且
,
,
成等比数列.
(1)求
的通项公式;
(2)求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6be3f864d60fc147b6905979403f3b2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e84c30444f13d37ada78285dc4f83b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eca7e7b23fd74e3cf89ac541cb7a5d88.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba80577ba05aeeef885884f444ba1e0d.png)
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6 . 设数列
满足
,
,且
,若
表示不超过
的最大整数,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbec044a508bc046109e86def30d7490.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/7def23f30138e0b7c4c1e498d6903a6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50feb194b3a7cd2e437e15e0f6e2c3b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4f5908d6a1217e493ed7586b6964dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbec044a508bc046109e86def30d7490.png)
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名校
解题方法
7 . 已知
是等差数列,
,公差
.
(1)求数列
的通项公式;
(2)求数列
的前n项和的最大值,并求出对应n的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/008d0d4c22970d770c75589b380a37de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ddc6daf7e71ab940882c380f06e8908.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/83cf38189d5cbf627d2b82ac0eb76006.png)
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名校
解题方法
8 . 已知等差数列
的前
项和为
,且
,
.数列
中,
,
.则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdef06cffd632946bee883e34dfa9c7.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/3fde84802e22ec09383eeb5fa2218e9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9888a27d07f3a08109723fa25b60c3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/385275d29d8c8a7841eaeaa3dfab2cdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf47ea98fc093e7e2b5fd37a89350182.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdef06cffd632946bee883e34dfa9c7.png)
您最近一年使用:0次
9 . 数列
是等差数列,
是公比为
的等比数列,
是
的前
项和,已知
,
.
(1)求
的值;
(2)证明:将
按适当顺序排列后,可以成等差数列.
![](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/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.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/fc3d772eda3f0d489a5bc40ab501c35c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be5a36de2febe3a199198f33e5b92fdb.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(2)证明:将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca88d734fb81ff9dc6825defd2622fd.png)
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名校
解题方法
10 . 已知数列
为等差数列,公差为
,前
项和为
.
(1)若
,求
的值;
(2)若首项
中恰有6项在区间
内,求
的范围;
(3)若首项
,公差
,集合
,是否存在一个新数列
,满足①此新数列
不是常数列;②此新数列
中任意一项
;③此新数列
从第二项开始,每一项都等于它的前一项和后一项的调和平均数.若能,请举例说明;若不能,请说明理由.(注:数
叫做数
和数
的调和平均数).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0c2d1a12d12803534db0e52cb194489.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08c9965a04c2a6de04e949a15762f372.png)
(2)若首项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a79ad1addaf50a6159a55d9d0845a6fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65fee4e27b361e30d76db328b9048b49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
(3)若首项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae3012337aa392709349731fb1eef5b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c85144ca40f64972b8c94652f3926628.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6856c966ef5c9461552f681de2c48558.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b4dda7369edf57a39cfad583031328a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
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