已知等差数列
前5项和为50,
,数列
的前
项和为
.
(1)求数列
的通项公式;
(2)若数列
满足
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c103d1af236be75242e7184b53caec5.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/6fca45d1886b88832d6a8ecbd04b1972.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62e567d7e9761951a266953c8d5042ac.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74ed83735c6950ac33d4af2cee2c3c07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e8eff51e5a5d77e41a38bba48f19eb9.png)
2021高三·福建·学业考试 查看更多[2]
更新时间:2020-12-27 21:04:58
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解答题-问答题
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适中
(0.65)
【推荐1】已知函数
,数列
为等差数列,其中
,
为
的最小值.
(1)求
的通项公式.
(2)已知
是正项等比数列,
,
,求
的通项公式,并求
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17dda3a1bd83367abc5872797e424bb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c072bbf0571ce960b5e580a4192f4b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18156edebadef55784d134dd2cbf1df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86801504bd014e0bdba875176fa015cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.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/08eb71ecf8d733b6932f4680874dbbf3.png)
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【推荐2】已知数列
的各项均为正数,其前
项和为
,且
.
(1)求
,
;
(2)设
,求数列
的前8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/58e4898f6fbd7cd6e390445986e9c064.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/791b165c66aa396a418715523bf875af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2b473cf7630fde975298d5b2b8a09c6.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1】已知等差数列
的前
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,且__________.
(1)求
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的值.
在①
,
;②
;③18是
和
的等差中项,
.这三个条件中任选一个填在上面的横线上进行解答,若选择多个条件解答,按第一个解答计分.
![](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)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95e191086446263b7bbbd93613577c42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.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/108b48ccc84e631a508b274460feda8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
在①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6df1038200f2d97a52c716aab6c3bcb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d8b342e45701057b54207a39c864f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d45da9e16de7a3db417ae2e794313dd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4740344514cb6f1de52d3a2d8c3ee087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
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解答题-问答题
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适中
(0.65)
解题方法
【推荐2】若等比数列前
项和为
,比较
与
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b17a5a5064087b4f2281252473ff3be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1a60d73e20fb84f9c0955addb4b3621.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8895abc375de2697bab0830aa93f67d3.png)
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解答题-问答题
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名校
【推荐1】已知数列
的前
项和为
.
(1)证明:数列
为等差数列;
(2)设
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/340b185c7fb5caffa38cb4ead315b8d1.png)
(1)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/516670f18c82713d82d7bf6b68f1d509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039271f3111b0e21bc1282fcc22cf016.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】已知数列
的前n项和为
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(1)求数列
的通项公式;
(2)设
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的前n项和
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/783a612de358012484eb0ac3925914d7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb6eb2a0ef679a87b02e566e879a49a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fc5b76208b0e4655a7b5470f72b413f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次