已知数列
满足
,数列
的前
项和为
,若______,在以下三个条件中任选一个条件填入横线上,完成问题:
①
;
②数列
满足:
,
,且
的前
项和为
;
③
.
问题:求数列
的通项公式;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9645bd4d2002993b90ec6d48f9c04f7.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)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/929b412e16988cab6bc472fd0de4cda7.png)
②数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5879ea00e7f92302270d2ed9a460fe7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf9d4697c1ca0bfdc3985dcd04351222.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccdec1307529d0c6394a1bb7734aee11.png)
问题:求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
2021高三·全国·专题练习 查看更多[1]
(已下线)专题01 数列求通项(数列的前n项和与第n项的关系)-【解题思路培养】2022年高考数学一轮复习解答题拿分秘籍(全国通用版)
更新时间:2021-10-26 20:15:11
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】已知数列
的前
项和为
,且满足
,
.
.
(1)求数列
的通项公式;
(2)对于
,将数列
中落在区间
内的项的个数记为
,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/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a316124e688e76d6f330ffbea49d427d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9884f3b8d929904432782309923a022e.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)对于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13f9c04883e5d45d4baf4cdbf81e3aff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64019eb70caac556b3c14d07d73db216.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f64696f60c533ad95dc7890eb902741.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62c320a0619c63a5b650a1a94c0a5679.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7e74be91bfe4bc209da7539dbf9b72c.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】已知数列{an}是以2为公差的等差数列,a1, a2,a5成等比数列,数列{bn}前n项和为Sn,且Sn=n2+2n.
(1)求数列{an}和{bn}的通项公式;
(2)记
表示x的个位数字,如
, 求数列
的前20项的和T20.
(1)求数列{an}和{bn}的通项公式;
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eee49c86c7abaea7e4a306c1faa4b0f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02eb6239b6a63afec1ca31202890cfaa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f9a11c1c5079df8dda5682f222daba.png)
您最近一年使用:0次
【推荐1】已知数列
满足
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
(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/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cecb36665ae97f385fa4ce5726d8aa8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88ed6761eece8cbe4bfcd46c95283ae3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.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
【推荐2】记数列{an}的前n项和为Sn,对任意正整数n,有2Sn=nan,且a2=3.
(1)求数列{an}的通项公式;
(2)对所有正整数m,若ak<2m<ak+1,则在ak和ak+1两项中插入2m,由此得到一个新数列{bn},求{bn}的前40项和.
(1)求数列{an}的通项公式;
(2)对所有正整数m,若ak<2m<ak+1,则在ak和ak+1两项中插入2m,由此得到一个新数列{bn},求{bn}的前40项和.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】在数列
中,
为
的前
项和,
.
(1)求数列
的通项公式;
(2)设
,数列
的前
项和为
,证明
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](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/bba9671532cf17a5445e1985f6a47581.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58a7ebafaf12fec210ed243c1dbab94e.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/e672c3d231081d12e44a4211e5ac60bf.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】设
是数列
的前
项和,
.
(1)求
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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d031095c11620712639256ad38538df.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d622a4923d05e180df3206c7d08d5b59.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)
您最近一年使用:0次