1 . 已知
是正项数列
的前
项积,且
,将数列
的第1项,第3项,第7项,…,第
项抽出来,按原顺序组成一个新数列
,令
,数列
的前
项和为
,且不等式
对
恒成立,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.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/0b126acb59207c1478f317fd5e188879.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de777c4e44546bcfe26ad5b6bb418052.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5214be4ab4c116b6d8beb768db721cfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df57c4df55b1d63c5bfa330940a351ac.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380ddfd4e5671a323aae3c7074b233ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d12d0bd9afdd4e53ff37f5bfcaa1106c.png)
A.数列![]() | B.![]() |
C.![]() | D.实数![]() ![]() |
您最近一年使用:0次
名校
解题方法
2 . 已知数列
的前
项和
满足
,记
,数列
的前
项和为
,且对任意的
恒成立,则( )
![](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/8a29f39b208abece91e5acf117723dce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a21fa97e82bb67e263b94fa1612c157.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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32b89a80dbd80aaf5b6d25a914001320.png)
A.![]() | B.![]() |
C.![]() | D.![]() ![]() |
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3 . 已知数列
满足
,
,令
.
(1)求证:数列
为等差数列;
(2)设
,数列
的前n项和为
,定义
为不超过x的最大整数,例如
,
,求数列
的前n项和
.(参考公式:
)
![](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/e89bddd9c021a9caccc72cd0189e1ceb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e5fc0b571e6545e133d36af338733b6.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f0c1d9900e8c040d86a68deecb4a73d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ddad3d9fdb5e9951b6a1c31f9a72a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4f5908d6a1217e493ed7586b6964dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc995d4dc915fce7b9aa2a580a250d1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50b3bdab0058f097f736bbcb844442f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37c04c237a58b94d06952c208e18a5cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29a2b1ba86f57af9387eff5d8298cbef.png)
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解题方法
4 . 现有甲、乙两个盒子中都有大小、形状、质地相同的2个红球和1个黑球.从两个盒子中各任取一个球交换,记为一次操作.重复进行
次操作后,记甲盒子中黑球个数为
,甲盒中恰有1个黑球的概率为
,恰有2个黑球的概率为
.
(1)求随机变量
的分布列;
(2)求数列
的通项公式;
(3)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6368fec0c2c25db7c29b014d60270e97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93d0f3799612b81e85b87241ec8eee68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
(1)求随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/096b1ece1dcd29c59a46a4b3e02cb548.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e067aeb203bc5ce00c9dc47aa34cee5e.png)
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名校
解题方法
5 . 如图,已知正方体
顶点处有一质点
,点
每次会随机地沿一条棱向相邻的某个顶点移动,且向每个顶点移动的概率相同,从一个顶点沿一条棱移动到相邻顶点称为移动一次,若质点
的初始位置位于点
处,记点
移动
次后仍在底面
上的概率为
.
;
(2)求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc3612ef4132dfef2f8a4f5af22e89d8.png)
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名校
解题方法
6 . 设
,
.
(1)当
时,证明:
;
(2)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f77c845f50ab193151748aa67ea2b01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22dd8b3dc4c609bab82d356a5cc2208d.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/200f24e682c93e02a87f3f9d57dc5d40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9c599e8d420006448905acec2b8234.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fad32850af0f1dd8b57e9ad01868f7f.png)
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7 . 11分制乒乓球比赛,每赢一球得1分,当某局打成
平后,每球交换发球权,先多得2分的一方获胜,该局比赛结束.甲、乙两位同学进行单打比赛,假设甲发球时甲得分的概率为
,乙发球时甲得分的概率为
,各球的比赛结果相互独立.在某局比赛双方打成
平后,甲先发球.
(1)求再打2球该局比赛结束的概率;
(2)两人又打了
个球该局比赛结束,求
的数学期望
;
(3)若将规则改为“打成
平后,每球交换发球权,先连得两分者获胜”,求该局比赛甲获胜的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db3c3ffbae2f4ed36909dca6aecbad18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db3c3ffbae2f4ed36909dca6aecbad18.png)
(1)求再打2球该局比赛结束的概率;
(2)两人又打了
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
(3)若将规则改为“打成
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db3c3ffbae2f4ed36909dca6aecbad18.png)
您最近一年使用:0次
8 . 已知数列
是公比大于0的等比数列.其前
项和为
.若
.
(1)求数列
前
项和
;
(2)设
,
.
(ⅰ)当
时,求证:
;
(ⅱ)求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.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/6ff14226c25417181e3daab4b157096f.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2a471526dab88625f06b7708cd7b991.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c73e4aa3454443728cd5e6e24d9f839c.png)
(ⅰ)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca4bfbc02ee7a09136dd3c0db55c8a6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/268a83236c72c04376c3686016a309c5.png)
(ⅱ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbe5f87926e73c8c0fa2df903a964bb7.png)
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9 . 设数列
的前
项和为
,
,
,若
,则正整数
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.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/0ea8d0e50065114b05ef2dc1ea1129cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c840b24a1626f247eefe7371c8abb50e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f16c5c6c416370c28c70dfb9fe1d769f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
A.2024 | B.2023 | C.2022 | D.2021 |
您最近一年使用:0次
名校
解题方法
10 . 已知首项为1的数列
的前
项和为
,其中
,现有以下结论:①
;②
;③
.则正确结论的序号为( )
![](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/5de33eee3f30cd929620f7f52069c894.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f801629bc14181f7e0cd2aa67c22b527.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb0eda61a7d9fc046aac897b6073c52b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abf15ab668060c0fc89a73dbfd57d5f.png)
A.① | B.② | C.②③ | D.①②③ |
您最近一年使用:0次