1 . 已知等差数列
的首项为1,前
项和为
,且
是3与
的等比中项.
(1)求数列
的通项公式:
(2)若
是数列
的前
项和,求
的最小值.
![](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/eb0f10a8a67a3b6c595745f9a82b45b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d29ed246168b03ba97deedbd0c26d373.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba57c83d526ac308d1461e80fcca9f36.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
昨日更新
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125次组卷
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2卷引用:上海市宝山区2023-2024学年高二下学期期末教学质量监测数学试卷
名校
2 . 已知数列
是等比数列,且
,则
的值为_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71bf2892b6dd5b5b776e3d7f549e8cbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b534c733e225e7ba8a11c4dab38e672.png)
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解题方法
3 . 正项等比数列
中,
与
是
的两个极值点,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/972a067d9d035b9be7768a2e23dee986.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e29f6ffe091d4f51b3b7c8c9ca88005.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c74fd9b94d7e7c54207580a3823b381a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/972a067d9d035b9be7768a2e23dee986.png)
您最近一年使用:0次
名校
4 . 已知各项均不相同的等差数列
的公差为
,且满足:
,
,
成等比数列,则
的值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc858b7a95c5006a44067022da09f667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09e151e8083936ff799a0f27c54704d9.png)
您最近一年使用:0次
解题方法
5 . 已知等比数列的前
项和为
,则
的值为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe2a7c19ce0b08dbaaa8a90c18929295.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
解题方法
6 . 已知等差数列
的公差不为零,
,且
成等比数列.
(1)求数列
的通项公式;
(2)
为数列
的前n项和,试判断当n取何值时,
最大,并求出最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96c41befd9ad431dc8cd0df351b51080.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4d65572deddbc763c71141322bfbedb.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
7 . 判断下列命题,把正确的命题序号写在横线上:__________ .
(1)实数2,8的等比中项为4;
(2)若
为等差数列且前n项和为
,则
是等差数列;
(3)已知数列
前n项和
,则
为等比数列;
(4)已知
为等比数列,则数列
是等比数列(其中
);
(5)若数列
满足
,则数列
为等差数列.
(1)实数2,8的等比中项为4;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dea1dd4ffcb4cf0697ca43079f6a1f2.png)
(3)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27e1f70fb9ac4b3c7f04e18c673eca5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(4)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/181778bd8a2503690e92bd09a61af75d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33f306d2b261f4c39a9fc0858d96e647.png)
(5)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7266459b6116ed35d57cc8fa54df8282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次
名校
8 . 已知等比数列
的公比为
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0382b4a2ab0657d2d6830bb6be2b17b6.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa72e890c07465c73c6f4c9d9476e02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0382b4a2ab0657d2d6830bb6be2b17b6.png)
您最近一年使用:0次
解题方法
9 . 在公差
不为零的等差数列
中,
成等比数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36956c135e05ac7223f2c8cc45f7671d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
您最近一年使用:0次
10 . 对于命题:①存在
、
、
的某个排列,使得对任意
,这三个数均不能成等比数列;②对
、
、
的任意排列,均存在相应的
,使得这三个数成等差数列.下列判断正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7980e96d332aa0b4ed25c2dbff79b366.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45b8b77522dfc890b99f0a86a690de94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc24d605ad707ad0e76059d8a31f50d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5caabda288fc01cc168938846eec5d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7980e96d332aa0b4ed25c2dbff79b366.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45b8b77522dfc890b99f0a86a690de94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc24d605ad707ad0e76059d8a31f50d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5caabda288fc01cc168938846eec5d2.png)
A.①和②均为真命题 | B.①和②均为假命题 |
C.①为真命题,②为假命题 | D.①为假命题,②为真命题 |
您最近一年使用:0次