已知数列
各项均为正数,
,
,且
.
(1)若数列
为等差数列,求数列
的前
项和
;
(2)若数列
为等比数列,且数列
不为等比数列,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2798e1dcab1f7f0fe3b8a94b3cd6a88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7cf5b05079676470d48e846d3277e67.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d82c65a855b1eed9c43e6829f6c3bffb.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)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40dc43b8d11d5462e4b525dd7b03bcfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
更新时间:2023-06-18 06:19:34
|
相似题推荐
【推荐1】已知数列
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,
,其中
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的前
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(1)证明数列
为等比数列,并求数列
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(2)令
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(1)证明数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e2de706dc5f0439b989273a5367f63a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a10d0e42725b1d248f07f51f6691f78.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a24bf180586649e329f5916207fe07e.png)
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解答题-问答题
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适中
(0.65)
名校
【推荐2】设数列{an}的前n项和为Sn.已知a1=a (a≠3),an+1=Sn+3n,n∈N+.
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(2)若an+1≥an,n∈N+,求a的取值范围.
(1)设bn=Sn-3n,求数列{bn}的通项公式;
(2)若an+1≥an,n∈N+,求a的取值范围.
您最近一年使用:0次
【推荐1】在等比数列
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,
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(I)求数列
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(II)设数列
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解答题-证明题
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适中
(0.65)
解题方法
【推荐2】在
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f2273150c1029c80436c752a8e1569.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c21abad0862e99c042fe51ebde27b142.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6402f1010e94be78552ed4c45548b1b8.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee14312eec42c729aab9880e09d3726.png)
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【推荐1】已知等差数列
的前
项和为
,且
,
.
(1)求数列
的通项公式;
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,若
,
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63c6e0c2d16cda7e8b2b8c588adeb8ae.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/a8a0eecb5b800fce9ae10aed86ffee62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5170584604571b5e1afd5ece941e2e73.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)等比数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87888c666bdeb939587d80b3f38902c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/012f1e5df0528c0f9a5754b7dc84424e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02b25850823f9366760bbb8326b134e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5344eadd4711db34e3f935aedd5fb270.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
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适中
(0.65)
解题方法
【推荐2】已知在等差数列
中,
,
,且
,
.
(1)求数列
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(2)求数列
的通项公式和前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e913fa0f5722a70180783765f6d990bf.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37933cfc60b4bd29f1684687ddd2cbd4.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次