1 . 在数列
中,
,
,
,记
的前n项和为
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c68b253787b7980d259a243ee42ecfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/930bc56406e69b785b37a83d48e36724.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174d8a8c6b4a53ad17d4128928af88d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
A.若![]() ![]() ![]() | B.若![]() ![]() ![]() |
C.若![]() ![]() ![]() | D.若![]() ![]() ![]() |
您最近一年使用:0次
2 . 已知等差数列
的前
项和为
,且
.
(1)求数列
的通项公式;
(2)数列
满足
,令
,求证:
.
![](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/3dfa129c3f8f9d41cc175c9c23790ed7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4995fa0403e013d888c0935ebfe15024.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9356245b78a281f18b5d0d618e5387f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01f6e795a55ff3ecd973858aadd9ff05.png)
您最近一年使用:0次
2024-05-04更新
|
2403次组卷
|
2卷引用:浙江省杭州市2024届高三下学期4月教学质量检测数学试题
3 . 已知数列
的前
项和为
,且满足
.
(1)当
时,求
;
(2)若
,设
,求
的通项公式.
![](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/c99a1aa3faf7df5fc06af26697ec3b30.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8e69866076dcff686a05e9e91e61e68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3cf6f2bbe20a404fea41a4d2b1c4c7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8ce45899b363a29694c19c4238afc2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ac8e1d60f036093acd1e8fb476226b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
您最近一年使用:0次
解题方法
4 . 已知各项都是正数的等比数列
的前3项和为21,且
,数列
中,
,若
是等差数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80e714bab58ef7d55e9ea809d667e1df.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f0939caf47d751f8c7139bd0b25fe98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22f4af06d11d85f30ed9821682ef7a82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5344eadd4711db34e3f935aedd5fb270.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80e714bab58ef7d55e9ea809d667e1df.png)
您最近一年使用:0次
5 . 已知数列
是等差数列,且
,
,则数列
的公差
是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/894aaec56149f880c7cf2bbc0f358d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a39dabf1d2cb4094bd2178576970d29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/894aaec56149f880c7cf2bbc0f358d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
6 . 设等差数列
的前
项和为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7999465d0e871febde66296a0cbf058c.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/0b389a8bea18b8a276a448b1b2f7342d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7999465d0e871febde66296a0cbf058c.png)
您最近一年使用:0次
2024-04-24更新
|
688次组卷
|
3卷引用:陕西省安康市高新中学、安康中学高新分校2023-2024学年高三阶段性测试(八)理科数学试题
解题方法
7 . 已知
是等差数列,
是等比数列,且
的前n项和为
,在①
,②
这两个条件中任选其中一个,完成下面问题的解答.
(1)求数列
和
的通项公式;
(2)设数列
的前n项和为
,是否存在
,使得
若存在,求出所有满足题意的
;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274191cca23e72fa887829f4527e98c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16ff8ce3e59c069490084ffc200cfda9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47a99b841116f01b845a324da81d786c.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2767882820f4ba0defde0e412adb747f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d38b6286e5f74b604b9fb639c55d611f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0137430ff7d1753310cf17a5f0e58b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
您最近一年使用:0次
名校
8 . 在等差数列
中,
,则
的前19项和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e45f4fdc859dbc3c62b5f7006a8fa35a.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea4429a287b7e5e8c7a32b818d024be0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e45f4fdc859dbc3c62b5f7006a8fa35a.png)
您最近一年使用:0次
2024-04-23更新
|
574次组卷
|
2卷引用:内蒙古自治区呼伦贝尔市2024届高三下学期二模理科数学试题
名校
9 . 记
为等差数列
的前
项和,已知
,
,则
取最小值时,
的取值为( )
![](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/d1bdf6054ecdabf2c16f485f938963fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6550a969a59254ef516fef64752b6098.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
A.6 | B.7 | C.7或8 | D.8或9 |
您最近一年使用:0次
2024-04-22更新
|
798次组卷
|
4卷引用:四川省泸州市2024届高三第三次教学质量诊断性考试(理科)数学试题
10 . 记等差数列
的前
项和为
,
是正项等比数列,且
.
(1)求
和
的通项公式;
(2)证明
是等比数列.
![](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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/738639bed93112168095c6e96df7c350.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae99a02a5fda4c6138f273f3e612ac48.png)
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