已知等比数列
的各项均为正数,且2a1+3a2=1,a32=9a2a6,等差数列
满足b2=5,b6+b8=30.
(Ⅰ)求数列
的通项公式;
(Ⅱ)求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(Ⅰ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62e567d7e9761951a266953c8d5042ac.png)
(Ⅱ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9092acd43e90e75868e90a21e0cc1f09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
20-21高二·全国·单元测试 查看更多[1]
(已下线)第四章 数列(提高卷)-《阳光测评》2020-2021学年高二数学单元提升卷(人教A版2019选择性必修第二册)
更新时间:2021-10-06 19:36:28
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相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】已知
是等差数列,设数列
的前n项和为
,且
,
,又
,
.
(1)求
和
的通项公式;
(2)令
,求
的前n项和
.
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea886c1907cc91e8d56c7713b86eb14c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2dcd9dce9e95d00fb3569390faac22e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ff6ea776d6adbb0c4be62196d6c041c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cff456ec5e6715f4c753e7e5d33ef116.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7cb579c6c57a458026f4e192c52b958.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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【推荐2】在①
,②
,③
这三个条件中任选一个,补充在下面问题中,并解答问题:已知正项等差数列
的公差是等差数列
的公差的两倍,设
、
分别为数列
、
的前n项和,且
,
,________,设
,求
的前n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/5032706dd285c22e149c675da465d9ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a5527f23f70f390fc81b925338594be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c62b575607722d4b98e721f13b79a4e7.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8890769a19ffa101e95d672c4a343d1.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/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69b4e688ad5156121531f6e0f4b4c1eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38d98410f0f650449c5bdc0d84149103.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3cfeacc29e6a61c5b3b4e439c0a91df.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】设
为等比数列
的前
项和,已知
成等差数列.
(1)求数列
的通项公式;
(2)设
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](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/4355827844a3eada88adb749fc9ced20.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb6eb2a0ef679a87b02e566e879a49a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92fe64a9c4fc3e26a134d9f648c0026e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
解题方法
【推荐2】某市为控制大气PM2.5的浓度,环境部门规定:该市每年的大气主要污染物排放总量不能超过55万吨,否则将采取紧急限排措施.已知该市2013年的大气主要污染物排放总量为40万吨,通过技术改造和倡导绿色低碳生活等措施,此后每年的原大气主要污染物排放量比上一年的排放总量减少10%.同时,因为经济发展和人口增加等因素,每年又新增加大气主要污染物排放量
万吨.
(1)从2014年起,该市每年大气主要污染物排放总量(万吨)依次构成数列
,求相邻两年主要污染物排放总量的关系式;
(2)证明:数列
是等比数列;
(3)若该市始终不需要采取紧急限排措施,求m的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f93a232c88870d213a7b74a796a1ff4b.png)
(1)从2014年起,该市每年大气主要污染物排放总量(万吨)依次构成数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcf0315936783910f9a8bd330e2ea5ee.png)
(3)若该市始终不需要采取紧急限排措施,求m的取值范围.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】已知数列
}满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/879f2cbe4fe7e392d3af5b9d4d9544ae.png)
(Ⅰ) 试求
的值;
(Ⅱ)记数列
的前
项和
,若对
恒有
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/879f2cbe4fe7e392d3af5b9d4d9544ae.png)
(Ⅰ) 试求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b94596e2d955050a7b56052d6efdc422.png)
(Ⅱ)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6da44fd766c35eef8b00c50eedb5fb53.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/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62539a50ef0fd1d7634b3830a0f3d994.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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【推荐2】已知数列
满足
(
),其中
为
的前
项和,
.
(1)求数列
的通项公式;
(2)记数列
的前
项和为
,是否存在无限集合
,使得当
时,总有
成立?若存在,请找出一个这样的集合;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66cec75ddab6e99eba4c7f5ad56f24db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.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/039e4fe671d61e59b96ee525c9df43e8.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41cf1da18d91f7c98086553d157d1a87.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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa9b6ad6f6fce0c84edfbc7b9802e3d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26834885544e74f5c2d0d7a4d2e00d34.png)
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