名校
1 . 已知二次函数
的图象的顶点坐标为
,且过坐标原点
.数列
的前
项和为
,点
在二次函数
的图象上.
(Ⅰ)求数列
的通项公式;
(Ⅱ)设
,数列
的前
项和为
,若
对
恒成立,求实数
的取值范围;
(Ⅲ)在数列
中是否存在这样一些项:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b338721e124048b547d3268a67ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edaaab658512ef8356e228879582cf94.png)
,这些项都能够构成以
为首项,
为公比的等比数列
?若存在,写出
关于
的表达式;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5f2932b9863fb218b7a990aa80abfc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.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/b8df5cca91bbd56bd8c68d3a9f87012e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
(Ⅰ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
(Ⅱ)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc0c5e305fdd6773ca9d5ce1d1fb4368.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.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/255afadbbd30a385b4a433f95b27962d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/851c8763f6700bccac95949fc0d316f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
(Ⅲ)在数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b338721e124048b547d3268a67ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edaaab658512ef8356e228879582cf94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756b5423a1ef40732567e3b18098270f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a1cd8452683923f3fcade9034f78a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e956b81c5f97904f3d7c0843c717cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d55a7d201b7336a2b950c7fb05409bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
2016-12-03更新
|
1825次组卷
|
5卷引用:2015届北京市顺义区高三第一次统一练习(一模)理科数学试卷
2015届北京市顺义区高三第一次统一练习(一模)理科数学试卷上海市行知中学2018-2019学年高三上学期期中数学试题江西省南昌八中、南昌二十三中等四校2018-2019学年高一下学期期中联考数学试题(已下线)考向18 数列不等式-备战2022年高考数学一轮复习考点微专题(上海专用)(已下线)专题17 数列探索型、存在型问题的解法 微点1 数列探索型问题的解法
11-12高三上·北京·阶段练习
解题方法
2 . 已知数列
的前
项和,
.
(1)求数列
的通项公式
;
(2)记
,求
.
![](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/ab38a7ec3ae3e1f4e771e78bbd9e04d0.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b041c471e68930874f4ed16d883ccb8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
9-10高一下·浙江宁波·期中
3 . 已知点(1,
)是函数
且
)的图象上一点,等比数列
的前n项和为
,数列![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/4f9cd772a032469a973b2f67cf1f10de.png)
的首项为c,且前n项和
满足
-
=
+
(n
2)
(1)求数列
和
的通项公式;
(2)若数列{
前n项和为
,问
>
的最小正整数n是多少?
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/bd053d180c6d44cca8a52c60ba8770c9.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/f59756cde9e74e808c7f5210d29565a4.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/7c23e5b3cae84a9e84d65df17f3e94f1.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/2a1432b443854a3996f12909813f8012.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/0cb62dd690cb490eb5d11f83d954bde7.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/4f9cd772a032469a973b2f67cf1f10de.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/307f0833a2d54775b016728c5e005434.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/bb2366244dab470fa03eaa30c78820e4.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/bb2366244dab470fa03eaa30c78820e4.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/6c1f857f513447879f8dcb1cee5293f7.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/f649b06f3bc543b585c0cec42a09e422.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/23ffe3a83dda4af4820cd3f08911a983.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/bc5086e18abd4161a2bdfc2970411e42.png)
(1)求数列
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/2a1432b443854a3996f12909813f8012.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/4f9cd772a032469a973b2f67cf1f10de.png)
(2)若数列{
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/d5fcf2dcd4cc49a2a8742ab25b423044.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/da290bd016a44efe92365fee7d65a3c4.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/da290bd016a44efe92365fee7d65a3c4.png)
![](https://img.xkw.com/dksih/QBM/2011/3/16/1570042175807488/1570042181271552/STEM/95d3d758e8824b73b26a0b6098a4a179.png)
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