在数列
中,
,
,点
都在直线
上.
(1)求数列
的通项公式.
(2)若
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f28171b364c85b51806eddb2c210cc1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a316124e688e76d6f330ffbea49d427d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4976cb432a52c2316bc7dad303474c0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae96f5020aef5aef03ec7f406460f608.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3a17251e019a16a40a520c3dc2fac74.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
更新时间:2023-01-31 18:31:01
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】已知等差数列
的前
项和为
,
,
.
(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/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/19e350f0a7d20ff94d330434c4be6e23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc91e27c7410472197be18c0ed2ebb3f.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18ec386f0f3ddad65efa9fac2d5bc5d0.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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真题
【推荐2】已知公差不为0的等差数列{an}的首项a1为a(a∈R)设数列的前n项和为Sn,且
,
,
成等比数列.
(1)求数列{an}的通项公式及Sn;
(2)记An=
+
+
+…+
,Bn=
+
+…+
,当n≥2时,试比较An与Bn的大小.
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/94f40ad913f546fc821cdb6e941afc41.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/f260637caae04f27a7eb1754c3f2e860.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/94012950fb96409fbbee29219853e0b1.png)
(1)求数列{an}的通项公式及Sn;
(2)记An=
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/7c38967ee8714a1f9f9966a326557a9c.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/d8638e814c3043378bd5e6c8f830ab09.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/f5421ade01e7498fa431308b6d8ddd37.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/835eb7edfbfd486caf87a8c845375ed4.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/6df06dbd15254d2290113a37844c6777.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/c1a8bf0598a6447f9f198f3521fe3f08.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743379578880/1571743385305088/STEM/e1edd421dbc8497e9e64fd4a49fa0e2c.png)
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解答题-证明题
|
适中
(0.65)
【推荐1】已知函数
,数列
中,若
,且
.
(1)求证:数列
是等比数列;
(2)设数列
的前
项和为
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1568a2c254127c40ab65ea7b774acce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c6aa8089b5d9b722aff679af3c4d289.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2438f2272d7b7ab51dbbe587025a553d.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/213e22890204937a5dded4436369390f.png)
(2)设数列
![](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/fc1f5d407c0e99344ed5f0f5926c5d22.png)
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名校
解题方法
【推荐2】已知等比数列
的前n项和为
,
,且
,
,
成等差数列.
(1)求数列
的通项公式;
(2)设
,求数列
的前n项和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c6a8306b8075ad9ce84d9114d086961.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dbf80cb71406fd14621139149f7ed9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/496b12437ca67b61453b28480ad7aaaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77c7cbefb0c85d88a5096b4af9e703d4.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1227ebe642586ad76c344db8ce8fc90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee4464b3b4eb6e52ee02f095aae84f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb26cd1601fe7e76e1e2dc0b4909324a.png)
您最近一年使用:0次
解答题-问答题
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适中
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【推荐3】为保护长江流域渔业资源,2020年国家农业农村部发布《长江十年禁渔计划》.某市为了解决禁渔期渔民的生计问题,试点推出面点、汽修两种职业技能培训,一周内渔民可以每天自由选择其中一个进行职业培训,七天后确定具体职业.政府对提供培训的机构有不同的补贴政策:面点培训每天200元/人,汽修培训每天300元/人.若渔民甲当天选择了某种职业培训,第二天他会有0.4的可能性换另一种职业培训.假定渔民甲七天都参与全天培训,且第一天选择的是汽修培训,第
天选择汽修培训的概率是
(
,2,3,…,7).
(1)求
;
(2)证明:
(
,2,3,…,7)为等比数列;
(3)试估算一周内政府渔民甲对培训机构补贴总费用的数学期望(
近似看作0).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb5c607987b73502db63f77c9799f4bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c45176df950dfe48b8ca7eac08ee349.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87b21b872313f7d8c5b606981f954a1e.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d397c7e6be852f8139ba7ca72f28da56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c45176df950dfe48b8ca7eac08ee349.png)
(3)试估算一周内政府渔民甲对培训机构补贴总费用的数学期望(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa531ee4cc9d25e274603b9e8bee24c5.png)
您最近一年使用:0次
【推荐1】已知数列
,
,满足
,
.
(Ⅰ)令
,证明:数列
为等差数列,并求数列
的通项公式;
(Ⅱ)若
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d4c97716e4fbf8c5794ad9dfb5191ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c800562a3f83b1594567ad211e41471.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/948f39334fbedeb849be39552aa00c4c.png)
(Ⅰ)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25c2a5f8ec179b72b201c3c0a670612a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e93d5a8d308095f977bbf2fcb9554c3e.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)
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】已知等差数列
的前
项和为
,且
,
.
(1)求数列
的通项公式;
(2)求数列
的前
项和
.
![](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/af49e650241140fea4f1f78f7769e262.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36183db0759eec0e108274d229fcd00b.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/5e6603814ac39b169453607671158d3b.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