名校
解题方法
1 . (本小题满分16分)
已知数列
的前
项和为
,且满足
,数列
的前
项和为
,且满足
,其中
N*.
(1)求数列
的通项公式;
(2)若数列
是公差不为零的等差数列.
①求实数
的值.
②若
≤
对任意的
N*恒成立,求
的取值范围.
已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.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/60965815aa04043db051b7bd89eda80d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0213618a5d387fe37099f954e69b8ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5b0aafc603ba02b6702e785b00a5013.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
①求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e05ad029d2bfa4a4349bf78ac90f6803.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5b0aafc603ba02b6702e785b00a5013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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解题方法
2 . 已知等差数列
的首项为
,公差为
,等比数列
的首项为
,公比为
,其中
,且
.
(1)求证:
,并由
推导
的值;
(2)若数列
共有
项,前
项的和为
,其后的
项的和为
,再其后的
项的和为
,求
的比值.
(3)若数列
的前
项,前
项、前
项的和分别为
,试用含字母
的式子来表示
(即
,且不含字母
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63ea79e5b52c82c9b5bc188e150ecd8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/543150ec61b3177fbb45b7e1d9800765.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/663408ffd10ad082002513bd472118c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a9b4d7a50cac0f712c6bb644f5e07e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43f41be870e84c819362787849770519.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b9a672337c7a5d00e55581bb265aba0.png)
(3)若数列
![](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/e2d51f9147b8265c0276c1f2c2659197.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43f41be870e84c819362787849770519.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7cac25e2a2ca07a5b406de7d6c1752b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d307b3c4da63535e665ce0a17712eb47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4001ae6c447850b139a0206d28e02516.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
您最近一年使用:0次
2020-01-14更新
|
489次组卷
|
3卷引用:上海市北虹、上理工附中、同二、光明、六十、卢高、东昌等七校2016-2017学年高三上学期12月月考数学试题
上海市北虹、上理工附中、同二、光明、六十、卢高、东昌等七校2016-2017学年高三上学期12月月考数学试题上海市七校2017届高三上学期12月联考数学试题(已下线)专题7 等比数列的性质 微点2 等比数列前n项和的性质
13-14高三·江苏苏州·阶段练习
解题方法
3 . 设数列{an}满足
.
(1)若a1=3,求证:存在
(a,b,c为常数),使数列{an+f(n)}是等比数列,并求出数列{an}的通项公式;
(2)若an是一个等差数列{bn}的前n项和,求首项a1的值与数列{bn}的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7e1283865fa0ec060f5aacfb36d3958.png)
(1)若a1=3,求证:存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d2d9e07fe79fe89e3646feda7f295d6.png)
(2)若an是一个等差数列{bn}的前n项和,求首项a1的值与数列{bn}的通项公式.
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