名校
解题方法
1 . 对于数列
,若存在正数
,使得对任意
,
,都满足
,则称数列
符合“
条件”.
(1)试判断公差为2的等差数列
是否符合“
条件”?
(2)若首项为1,公比为
的正项等比数列
符合“
条件”.求
的范围;
(3)在(2)的条件下,记数列
的前
项和为
,证明:存在正数
,使得数列
符合“
条件”.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b04c7ba0ffd54e60b2829f4440c91ec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7d9712c3b25f3030e166e136d3a4686.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38e103afdf96430454d8409592a2c4e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aca3fafacd6a4d9df495f3563d22c286.png)
(1)试判断公差为2的等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71a390a0f7b1073ebeb024a225672a7e.png)
(2)若首项为1,公比为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd07cd3600f1b5ab12e079890630edcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(3)在(2)的条件下,记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/6ed1e9cdd5a82f29ec89b2c53b4fa6f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce224c28ca451c4f105dc3b077736cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cba3bb73f0c643c79b53db038c3706a.png)
您最近一年使用:0次
2023-02-07更新
|
689次组卷
|
4卷引用:模块九 数列-2
名校
解题方法
2 . 若无穷数列{
}满足如下两个条件,则称{
}为无界数列:
①
(n=1,2,3......)
②对任意的正数
,都存在正整数N,使得n>N,都有
.
(1)若
,
(n=1,2,3......),判断数列{
},{
}是否是无界数列;
(2)若
,是否存在正整数k,使得对于一切
,都有
成立?若存在,求出k的范围;若不存在说明理由;
(3)若数列{
}是单调递增的无界数列,求证:存在正整数m,使得
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9645bd4d2002993b90ec6d48f9c04f7.png)
②对任意的正数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/700458c01a7ad031e27d80ed43e9e882.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2a701eb81a1e88c69357f9eae5915ee.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ff1c33b81ac2f065d37faef37504bb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee912af5e2313d631ff3016ca7cc32d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ff1c33b81ac2f065d37faef37504bb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4fef5f2a4235817fb704d29e08766e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bec3181d9f88a68fb7470d0c9beb183.png)
(3)若数列{
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7407503edea1b02e3084387c8a328d9e.png)
您最近一年使用:0次
2022-03-31更新
|
1120次组卷
|
8卷引用:临考押题卷01-2022年高考数学临考押题卷(北京卷)
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