题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180915-57374.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180916-33532.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180916-23165.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180916-97467.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180916-51079.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180915-57374.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-65959.png)
(1)求
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-49071.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-39119.png)
(2)求数列
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180915-57374.png)
(3)设
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-90161.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180916-33532.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-24157.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-86713.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-60518.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-35586.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-27361.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-97232.png)
解析
试题分析:(1)分别令
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-43415.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-79791.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-49071.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-39119.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180920-78168.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-65959.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180920-43406.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180920-26868.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-84880.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-54292.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-24157.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-34261.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-65959.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-86713.png)
试题解析:(1)令
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-43415.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-40476.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180922-41975.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-60518.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180922-91644.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180922-17050.png)
又因为数列
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-54292.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-60518.png)
令
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-79791.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180923-66346.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180923-18248.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-35586.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180923-95581.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180923-25900.png)
又因为数列
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-54292.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-35586.png)
(2)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-65622.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-29113.png)
由①
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-39065.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-63090.png)
化简得到
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-70192.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180925-95025.png)
由③
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180924-39065.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180925-12161.png)
化简得到
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180925-99312.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180925-85187.png)
当
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-79791.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180926-26319.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180926-86026.png)
所以数列
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-54292.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180926-45705.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180926-51905.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180927-13387.png)
(3)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180927-42938.png)
因为对任意的
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180927-85321.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-24157.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180928-83179.png)
化简得
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180921-34261.png)
当
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-65959.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180928-21106.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180928-28727.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180928-10048.png)
当
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180917-65959.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180929-95986.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180929-73020.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180929-34309.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180929-36463.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180918-86713.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180919-97232.png)
核心考点
试题【已知数列的各项都是正数,且对任意都有,其中为数列的前项和.(1)求、;(2)求数列的通项公式;(3)设,对任意的,都有恒成立,求实数的取值范围.】;主要考察你对数列的概念与表示方法等知识点的理解。[详细]
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180750-44073.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180751-36706.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180751-10378.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180649-36328.png)
①当a=5时,数列{xn}的前3项依次为5,3,1;
②对数列{xn}都存在正整数k,当n≥k时总有xn=xk;
③当n≥1时,xn>
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180650-63977.png)
④对某个正整数k,若xk+1≥xk,则xk=[
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007180650-63977.png)
其中的真命题有________.(写出所有真命题的编号)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007175435-57099.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007175435-80571.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007175435-21478.png)
A.6 | B.![]() | C.3 | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007175425-49791.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191007/20191007175425-49791.png)
A.11 | B.12 | C.13 | D.14 |
最新试题
- 1设数列{an}满足:a1=1,an+1=(n∈N*),(1)求a2,a3; (2)令bn=,求数列{bn}的通项公式;(
- 2如果一个多项式的次数是6次,那么这个多项式任何一项的次数( )A.都小于6B.都等于6C.都不小于6D.都不大于6
- 3关于科学家和他们的贡献,下列说法中正确的是 ( )A.安培首先发现了电流的磁效应B.伽利略认为自由落体运动是速度随位
- 4小刚经常随地吐痰、说脏话,同学们批评他不文明礼貌,他却说:“文明礼貌是我个人的事,与你们有什么关系?”请你对小刚的言行进
- 5小莉本学期数学平时作业、期中考试、期末考试的成绩分别是88分、82分、90分,各项占学期成绩分别为30%、30%、40%
- 6如图所示的水平传送带静止时,一个小物块A以某一水平初速度从传送带左端冲上传送带,然后从传送带右端以一个较小的速度v滑出传
- 7阅读下面一段文言文,完成7—11题。阮籍,字嗣宗,陈留尉氏人也。籍容貌瑰杰,志气宏放,傲然独得,任性不羁。博览群籍,尤好
- 8给你提供一张密度表,下列说法正确的是[ ]A.不用天平,只用量筒,能量出100g酒精 B.用量筒和水不能测量出实
- 9我国实现祖国和平统一的基本方针是A.一个国家,两种制度B.坚持一个中国原则C.和平统一,一国两制D.加强两岸交流与对话
- 10The student ________from the training so much that he was __
热门考点
- 1下列岩石中,哪一种可以找到化石?[ ]A、花岗岩 B、玄武岩 C、变质岩 D、砂岩
- 2下列对名著内容表述有误的一项是[ ]A.《伊索寓言》有不少故事是借动物的形象嘲讽人类的缺点的,像《蚯蚓和狐狸》《
- 3“三月三”歌节是我国哪个民族的传统节日?[ ]A.回族B.壮族C.朝鲜族D.傣族
- 4【题文】已知t为常数,函数在区间上的最大值为2,则实数 ▲ .
- 5 (填正确答案标号。选对1个得3分,选对2个得4分,选对3个得6分。每选错1个扣3分,最低得分为0分) (1)(6分)以
- 6阅读古诗,完成(1)~(2)题。己亥杂诗龚自珍浩荡离愁白日斜,吟鞭东指即天涯。落红不是无情物,化作春泥更护花。(1)诗歌
- 7计算:。
- 8下列词语没有错别字的一组是[ ]A.遨翔 莽莽沧沧 战战惊惊 鲲鹏展翅 B.匹敌 逍遥自在 荣辱毁誉 无所顾忌
- 9有一个“12V 6W”的小灯泡,如果接在36V的电源并要求能使其正常发光,必须______联一个______Ω的电阻,这
- 10属于战国时期经济发展新特点的是A.手工业中心冶铁业的出现B.灌溉技术的运用C.中原市场的形成与封建城市的兴起D.铁器、牛