题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231342-86222.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-45618.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-94150.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-72552.png)
(1)求通项公式
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-21531.png)
(2)求数列的前n项的和
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-75052.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-47548.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-35222.png)
解析
试题分析:(1)求通项公式
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-21531.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-45618.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-94150.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-72552.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-96676.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-79258.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-21531.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231342-86222.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-89041.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-96491.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-12098.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-97294.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231342-86222.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-72114.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231342-86222.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231343-21531.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-12599.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231342-86222.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-47548.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-12599.png)
试题解析:(1)当
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-96491.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231346-57871.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231347-20012.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231347-81587.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231347-97384.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231347-65047.png)
当
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231345-96491.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231347-35596.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231348-12880.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231348-29562.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231348-17747.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231348-24244.png)
综上
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231349-63471.png)
(2)由(1)得
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231349-58343.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231349-75641.png)
所以
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231349-59722.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231344-98790.png)
核心考点
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231238-96106.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231238-98293.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231238-84197.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231238-93277.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231239-78419.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231239-55591.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231239-25630.png)
(1)求
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231239-30024.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231240-48763.png)
(2)求数列
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231238-96106.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231240-37718.png)
(3)设
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231240-97355.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231241-70752.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231241-44205.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231241-94912.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231241-70752.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231241-92910.png)
A.5 | B.7 | C.8 | D.7或8 |
p1:数列{an}是递增数列;p2:数列{nan}是递增数列;
p3:数列
![](http://img.shitiku.com.cn/uploads/allimg/20191011/20191011231217-86275.png)
其中的真命题为( ).
A.p1,p2 | B.p3,p4 |
C.p2,p3 | D.p1,p4 |
最新试题
- 1椭圆两准线间的距离是焦距的4倍,此椭圆的离心率为( )A.12B.13C.22D.14
- 2 读对联,注意揣摩其中的寓意。下边是某人根据自己的兴趣爱好题写的两幅对联,请写出此人具有哪些具体的兴趣爱好。(1)品韵
- 3下列有关各大洲说法,错误的是( )A.亚洲地势中部高,四周低B.欧洲是发达国家集中的地区C.非洲是黑色人种的故乡D.南
- 4阅读下面的文言文,完成后面的题目。豫让论明·方孝孺士君子立身事主,既名知己,则当竭尽智谋,忠告善道,销患于未形,保治于未
- 5 楚有祠者①,赐其舍人②卮③酒。舍人相谓曰:“数人饮之不足,一人饮之有余。请画地为蛇,先成者饮酒。”一人蛇先
- 6城市生态系统属于[ ]A.海洋生态系统 B.陆地生态系统 C.湿地生态系统 D.都不是
- 7下列有利于提高人口素质和控制人口增长过快的关键分别是( )A.少生、优生B.优生、少生C.晚婚、优生D.晚育、优生
- 8我国原有选举法规定:每96万农村人口选举1名全国人大代表,每24万城市人口选举1名全国人大代表。随着我国城乡经济社会快速
- 9“塔西佗陷阱”作为西方政治学的一个定律,用在政府公信力问题中,可表达为当政府不受信任的时候,政府怎样做都会受到公众的质疑
- 10质量为2kg的小球以4m/s的初速度由倾角为30°斜面底端沿斜面向上滑行,若上滑时的最大距离为1m,则小球滑回到出发点时
热门考点
- 1已知复数z满足(z+1)i=3+5i,其中i为虚数单位,则|z|=______.
- 2某商店统计了最近6个月某商品的进价x(元)与售价y(元)的对应数据如下表: 则回归直线方程是( )。
- 3“迷雾云遮难敞亮,宇寰久夜盼骄阳。柏宅楼上龙聚首,湘水岸边船启航。初战娄山标魄力,四夺赤水过长江。行程二万通华北,□□□
- 4achieve success, take part in, since then, disability, take
- 5关于某无色溶液中所含离子的鉴别,下列判断正确的是A.加入AgNO3溶液,生成白色沉淀,加稀盐酸沉淀不溶解,可确定有Cl—
- 6中共中央国务院批准的“五五”普法规划明确提出,要做好“12·4”全国法制宣传日活动,集中开展好以宪法为核心的法制宣传教育
- 7He turned around, but he couldn"t see _____. [ ]A. anyth
- 8阅读下列各首古诗,回答诗后问题。游山西村陆 游莫笑农家腊酒浑,丰年留客足鸡豚。山重水复疑无路,柳暗花明又一村。箫鼓追随
- 9最近科学家获得了极具理论研究价值的N4分子。有关N4说法正确的是A.N4和N2互为同素异形体B.N4是一种新型的有机物
- 10在1943年的开罗会议上,罗斯福总统与蒋介石进行了长时间的会谈,这令英国首相丘吉尔恼悔不已,他评价说:“英方与美方的会谈