复习专题《名词性从句》单元测试题(含答案) 含答案解析
复习专题《名词性从句》单元测试题(含答案) 含答案解析
一、初中英语名词性从句
1.____ he will offer us enough help doesn't matter a lot to our success.
A. If
B. Whether
C. Before
D. How
【答案】 B
【解析】【分析】句意:他是否提供帮助对于我们的成功没有什么关系。If不可以引导主语从句,故选B。
【点评】考查名词性从句,本题涉及whether引导的主语从句的应用。
2.While some behaviors may seem strange to you, remember you consider normal probably seems just as unusual to others.
A. it; that
B. what; that
C. that; what
D. which; that
【答案】 C
【解析】【分析】句意:虽然有些行为对你来说可能很奇怪,但请记住,你认为正常的行为对别人来说可能也不寻常。第一空为宾语从句,从句结构完整用that起连接作用,第二空为主语从句,从句中consider缺少宾语,应该用what,故选C。
【点评】考查名词性从句,本题涉及that引导的宾语从句和what引导的主语从句。
3.It matters little ______ a man dies, but _____ matters much is ______ he lives.
A. how; what; how
B. how; it; how
C. why; it; why
D. that; what; that 【答案】 A
【解析】【分析】句意:一个人如何死去并不重要,重要的是他如何生活。it为形式主语,how从句为真正的主语。What matters much (=the thing that matters much)。第一个how引导的是一个主语从句;it作形式主语;what引导的是主语从句;第二个how引导的是表语从句。故选A。
【点评】考查名词性从句,本题涉及主语从句和表语从句的应用。
4.____________ matters most in learning English is enough practice.
A. Why
B. That
C. Which
D. What
【答案】 D
【解析】【分析】句意:学习英语中最重要的是有足够的练习。A. why为什么;B. that引导名词性从句只起引导词作用,不充当成分;C. which哪一个;D. What什么。根据语境用what引导主语从句,并在句中做主语。故答案选D。
【点评】考查主语从句的引导词。主语从句属于名词性从句的一种,填哪个连接词要分析从句缺少什么成分,然后确定所选的词。
5.________ has been proved is that animals and insects have their own languages.
A. What
B. As
C. It
D. That
【答案】 A
【解析】【分析】句意:已被证明的是动物和昆虫有自己的语言。根据is判断,此处为主语从句,分析该从句,缺少主语,用what。选A。
【点评】考查名词性从句,本题涉及what引导的主语从句的应用。
6.They lost their way in the forest, and ________ made matters worse was that night began to fall.
A. that
B. it
C. what
D. which
【答案】 C
【解析】【分析】句意:他们在森林里迷路了,更糟糕的是天开始黑了。根据连词and可知,本句需要一个引导主语从句的连接词,该词同时还要能在从句里充当主语。that不能在句中作成分;it不能引导主语从句;which意为“哪一个”,不符合本句语境。排除A、B、D三项。故选C。
【点评】考查名词性从句,本题涉及what引导的主语从句的应用。
7.________ the weather will not clear up until next week is bad news for us.
A. As
B. If
C. Whether
D. That
【答案】 D
【解析】【分析】考查主语从句。句意:直到下周天气才放晴,这对我们来说是坏消息。此处是that引导的主语从句,that无实义,只其引导作用,故答案为D。
【点评】主语从句属于名词性从句,在名词性从句中,that无实义,只起连接作用,不做句子成分;if/whether起连接作用,不做句子成分,有实义“是否”。做题时注意看从句是否少成分。
8.It is a rule in his family that _______ comes home first should cook the dinner.
A. anybody
B. who
C. whoever
D. who that
【答案】 C
【解析】【分析】句意:在他的家里有个规定,就是先到家的人要先做饭。whoever 有两个词义:1no matter who,在这种用法时引导一个让步状语从句;2anybody that,在这种用法时,它连接一个名词性从句,在本题中它连接的是主语从句。这里就是第二个用法。所以选C。
9._______ is troubling me is ______ I don't understand ________ he said
A. What; that; what
B. What; what; what
C. That; that; what
D. Why; that; which 【答案】 A
【解析】【分析】句意:我烦恼的是我不明白他说的话。第一空是主语从句,从句中缺主语,要用What;第二空是表语从句,从句不缺成分,所以要填that;第三空是宾语从句,从句中的动词understand缺宾语,要填what。故选A。
【点评】考查名词性从句,本题涉及主语从句,表语从句和宾语从句的应用。10.—Tell me something about your adventure in the rainforest, please.
— We lost our way in the forest and ___ made matters worse was ___ night began to fall.
A. what; that
B. it; that
C. it; because
D. what; because
【答案】 A
【解析】【分析】考查名词性从句的连接词。第一空what作主语从句的主语;第二空为表语从句的that。
11.________ his failure lies is expected ________ clear to us.
A. What… to make
B. How… made
C. Where… to be made
D. Why… making
【答案】C
【解析】【分析】句意:他的失败之处有可能被我们弄清楚。分析句子可知,主语从句中的lie为不及物动词,所以主句中缺少状语,因此填where。expect sth.to do.固定短语,“期望某事发生”,sth. be expected to do.意为”某事有可能发生“。make sth. clear to sb为固定搭配,意为“向某人阐明某事,使某人弄清某事”。本句中make的宾语是where his failure lies 是被弄清楚,要用动词不定式的被动形式。因此选C。
【点评】考查名词性从句及固定搭配,本题涉及主语从句和固定短语expect sth.to do.
12.Located between the 16th and the 18th floor, ______ I call my “home” is more like a “bird's nest”.
A. which
B. that
C. what
D. where
【答案】 C
【解析】【分析】考查主语从句。What引导主语从句______ I call my “home”且 What在从句中充当call的宾语。故选C。
13.Has it been announced ______?
A. when are the planes to take off
B. that are the planes to take off
C. where are the planes to take off
D. when the planes are to take off
【答案】 D
【解析】【分析】句意: 飞机什么时候起飞已经宣布了吗?此处是when引导的主语从句,且要用陈述句语序,故选D。
【点评】考查名词性从句,it作形式主语,关系副词when引导的从句作真正的主语。
14.It________that the road will be closed tomorrow for repairs.
A. was announced
B. has been announced
C. had been announced
D. would be announced
【答案】 B
【解析】【分析】本题考查动词的时态和语态。题干句子中that到句子结束是宾语从句,且从句动词用“will+动词原形”表示将来,由此推断出空白处谓语动词应用现在的某种时态,在所给四个选项中,只有B项正确。
【点评】考查现在完成时的被动语态,其结构是have/has +been +done。需要注意宾语从句的时态。主句用现在时,从句所需的任何时态。
15.Some people believe _______ has happened before or is happening now will repeat itself in the future.
A. whatever
B. whenever
C. wherever
D. no matter what
【答案】 A
【解析】【分析】句意:一些人认为之前发生的或现在正在发生的任何事情在将来都会重复发生。Whatever has happened before or is happening now是一个主语从句,whatever既引导起这个主语从句,也在句中做主语。BC项都属于副词的性质,都不能做主语,通常只能做状语;no matter what只能用来引导状语从句,故选A。
【点评】考查名词性从句,本题涉及"特殊疑问词+ever"引导的主语从句。
16.________ is known to us all that the old scientist, for ________ life was hard in the past, still works hard in his eighties.
A. As; whose
B. It; whose
C. As; whom
D. It; whom
【答案】 D
【解析】【分析】句意:我们都知道,那位老科学家,过去生活很艰苦,到了八十多岁还在努力工作。第一空it is known to us all that…是个固定句型,意为“众所周知…”;第二空为介词+关系代词引导的定语从句,先行词the old scientist指人,作介词for的宾语,只能用whom,故选D。
【点评】考查名词性从句和定语从句,本题涉及固定句式it is known to us all that…和whom引导的限制性定语从句。
17. is clear to the members of the committee is that the President will not give in to their demands.
A. Who
B. It
C. As
D. What
【答案】 D
【解析】【分析】句意:委员会成员清楚的是,总统不会向他们的要求让步。that the President will not give in to their demands.这个句子作表语; is clear to the members of the committee这是主语从句,这里缺少主语从句的连接词,并且连接词在句中作主语,it是代词,不是了;连接词,故排除B;as作主语时,是在定语从句中,故排除C;who指人,根据表语指的事情,不是人,故排除A;what在主语从句中可以作主语或宾语,指事,符合句意,故选D。
【点评】考查名词性从句,本题涉及what引导的主语从句。
18.___ surprised me most was ____the girl passed the driver test.
A. That; that
B. What; how
C. What; that
D. That; why
【答案】 C
【解析】【分析】句意:最让我吃惊的是那个女孩通过了驾驶考试。___ surprised me most是一个主语从句,从句中缺少主语,故填what;____the girl passed the driver test 是一个表语从句,句中不缺少成分,故填that。因此选C。
【点评】考查名词性从句,本题涉及what引导的主语从句和that引导的表语从句。
19.It has been pointed out ________ plays a vital role in driving away one's anxiety is one's sweet childhood memories.
A. what that
B. which
C. that
D. that what
【答案】 D
【解析】【分析】句意:有人指出,驱除焦虑所起着至关重要的作用是童年美好的回忆。本句时一个主语从句,it作形式主语,真正的主语为that what plays a vital role in driving away one's anxiety is one's sweet childhood memories.,主语从句中又有一个主语从句,且此主语从句中缺少主语,所以用what引导。故选D。
【点评】考查名词性从句,本题涉及what引导的主语从句。
20.They lost their way in the forest, and ___ made matters worse was that night began to fall.
A. it
B. which
C. that
D. what
【答案】 D
【解析】【分析】本题中含有一个主语从句what made matters worse,其中的what引导起这个主语从句,同时在主语从句中做主语。AC两项不能引导主语从句,which在引导名词性从句的时候总是含有疑问的语义,而本句中并没有疑问的语义。句意:他们在森林里迷路了,情况更糟糕的是天又黑了。故D正确。
21.Pay no attention to those who laugh at you. What matters most is ________ you see yourself.
A. what
B. when
C. how
D. which
【答案】 C
【解析】【分析】句意:不要在意那些嘲笑你的人,最重要的是你如何看待你自己。本题考查表语从句,A.什么;B.当……时候;C.怎样;D.哪一个。根据句意,翻译成“如何”。故选C。
【点评】考查how引导的表语从句。
22.I never doubt .
A. whether this song is worth listening to
B. if this song is worth listening
C. that this song is worth listening
D. that this song is worth listening to
【答案】 D
【解析】【分析】句意:我从来没有怀疑这首歌值得去听。根据句子结构分析,本句是宾语从句,根据主句I never doubt,可知从句是陈述句,故排除A 和B,又因为listen to为固定搭配,故选D。
【点评】考查宾语从句。注意识记宾语从句的用法。
23.The question new measures should be taken to control the terrible air pollution is puzzles scientists a lot.
A. that; what
B. which; that
C. what; what
D. that; that
【答案】 C
【解析】【分析】句意为:应该采取什么样的新措施来控制空气污染的问题,是让科学家非常困惑的事情。第一空根据主语question,可知措施并不明确,应该指“什么样的new measures”,关系词应用what;第二空,be动词is后的表语从句缺少主语,应用关系词what,故选C。
【点评】考查同位语从句。注意that引导同住语从句时,在句中不做成分,也没有词义。
24.The place the bridge is supposed to be built should be the cross-river traffic is the heaviest.
A. which; where
B. at which; which
C. at which; where
D. which; in which 【答案】 C
【解析】【分析】句意:桥梁应该建在水上交通最繁忙的地方。定语从句,代指地方,用where/介词+which,根据the place,可知前面用介词at,表示在……地方,做地点状语,介词提前,因此用at which;根据 the cross-river traffic is the heaviest,可知是对桥所在地点的描述,因此用where,引导表语从句,故选C。
【点评】考查定语从句与表语从句的引导词。
25. doesn't matter you come or not.
A. That; whether
B. It; whether
C. That; if
D. It; if
【答案】 B
【解析】【分析】句意:你来不来无关紧要。根据句末or not,要用连词whether;有句子结构可知,此处是whether引导主语从句,放在句末,用it作形式主语。故选B。
【点评】考查连词和代词辨析。根据句子结构,选择正确的一项。
26.That is _____we were late last time.
A. that
B. when
C. why
D. what
【答案】 C
【解析】【分析】句意:这就是上次我们为什么迟到的原因。A.没有实际意义;B.当......时候;C.为什么;D.什么。为什么迟到,用why,引导名词性从句,做表语,故选C。
【点评】考查表语从句连接词用法,注意理解句意。
27.—I fell sick!
—I think it is _______ you are doing too much.
A. why
B. when
C. what
D. because
【答案】 D
【解析】【分析】句意:——我感觉不舒服。——我认为这是因为你一直做得太多。A.为什么;B.什么时候;C.什么;D.因为。做得太多是不舒服的原因,所以用because连接,故选D。
【点评】考查表语从句,注意理解句意。
28.—I'll have a ten-day holiday. But I don't know ________.
—How about Paris?
A. when to go
B. where to go
C. what to do
【答案】 B
【解析】【分析】句意:——我将有10天的假。但是我不知道去哪里?——巴黎如何?
A.when to go什么时候去,
B.where to go去哪里,
C.what to do做什么。根据后文提到去巴黎,可知是对地点提问,用where,填入where to go,故选B。
【点评】考查名词从句,注意where to go的用法。
29.Exactly _________ the potato was introduced into Europe is uncertain, but it was probably around 1565.
A. whether
B. when
C. why
D. how
【答案】 B
【解析】【分析】句意:土豆被引进欧洲具体的事件不被确定,但是可能是在1565年左右。根据时间状语round 1565得知这里是指时间不确定。故选B。
【点评】考查名词性从句,本题涉及when引导的主语从句。
30.It is still unknown how AI(人工智能)_______the way of our life as well as the world.
A. change
B. changed
C. will change
D. was changing
【答案】C
【解析】【分析】句意:人工智能将会怎么改变我们的生活方式和整个世界仍旧不为人所知。It是形式主语,真正的主语是后面how引导的从句,为主语从句。主句是一般现在时态,人工智能改变世界是没有发生的事情,用一般将来时态,其结构是will + 动词原形,故选C。
【点评】考查主语从句的时态。注意主句是现在时或者将来时,从句用任何需要的时态。
31._______ has not been decided next.
A. How to do
B. What to do next
C. To do what
D. To do how
【答案】 B
【解析】【分析】句意:接下来做什么还没有决定。根据助动词has可知前面是主语,what to do为名词性从句,可做主语,故选B。
【点评】考查名词性从句,识记名词性从句做主语的用法。
32.— Doctor, it seems ______ you like to work with animals.
— Yes, we should________ animals as our friends.
A. that; regard
B. what; be regarded
C. that; be regarded
D. what; regard
【答案】 A
【解析】【分析】句意:—医生,看起来你喜欢和动物一起工作。—是的。我们应该把动物看做我们的朋友。It seems + that从句,其中it 是形式主语,that引导主语从句。Regard---as---(把------看做------)。故选A。
【点评】此题考查主语从句和固定搭配regard---as---。
33.I know he's been curious about everything, but that's . Be patient!
A. what do kids like
B. what kids like
C. what are kids like
D. what kids are like
【答案】 D
【解析】【分析】句意:我知道他对每件事都充满好奇, 但这是小孩的样子。要有耐心。由题意知:That’s后跟的是一个表语从句, 从句要用陈述句语序, 所以A、C错了.B:what kids like 那是孩子喜欢的东西;D:what kids are like那是小孩的样子.like, 动词, 表示喜欢, 有时态变化形式;be like表示像, like是介词, like没有词形变化.对一切充满好奇是小孩的行为, 故选D。
【点评】表语从句。
34.I wonder .
A. how will you celebrate Thanksgiving
B. that the Water Festival is really fun.
C. what do people eat on the Mid-Autumn Festival
D. whether you will make resolution on New Year's Day
【答案】 D
【解析】【分析】句意:我想知道你是否将在新年做决定。A. how will you celebrate Thanksgiving你要怎样庆祝感恩节;B. that the Water Festival is really fun. 泼水节真的有趣;
C. what do people eat on the Mid-Autumn Festival中秋节人们叫什么?
D. whether you will make resolution on New Year's Day你是否会在新年做决定。Wonder后跟的是宾语从句,宾语从句要用陈述语序。A,C错了。Wonder:对……感到疑惑,想知道,后常跟一个含有“疑问”意义的宾语从句,B错。故选D。
35.It is clever ______ you ______ out the problem.
A. for; to work
B. of; working
C. for; working
D. of; to work
【答案】D
【解析】【分析】it可指代下文内容做形式主语,其主要有两种形式:1、It's + 形容词 + of + sb + to do sth.这个句型,形容词一般为sb的所具有的一种品质性格。2、It's + 形容词+ for + sb + to do sth.这个句型,形容词不是sb所具备的品质性格。句意:能算出这道难题,你真是太聪明了。结合语境可知选D。
【点评】it是人称代词,在句子中可以做形式主语,形式宾语,这是经常考察的内容,平时应注意总结,加强练习.
36.We believe ________ you have been devoted to ________ naturally of great necessity.
A. that; being
B. all that; be
C. that all; are
D. what; is
【答案】 D
【解析】【分析】句意:我们相信你所投入的当然是非常必要的。分析句子可知,believe 后接宾语从句,宾语从句中you have been devoted to缺少宾语,表示事物故用what;what you have been devoted to为主语,从句作主语,谓语动词用单数,故选D。
【点评】考查名词性从句和主谓一致,本题涉及what引导的主语从句和一般现在时。
37.—What impresses you most when you visit the Acropolis ?
— ________ it is that has brought the grand palace into today's terrible scene.
A. Where
B. What
C. How
D. When
【答案】 B
【解析】【分析】句意:——当你参观雅典卫城时,你印象最深的是什么?——使我印象最深的是什么将从前宏伟的宫殿变成了今天惨不忍睹的样子。强调句型的特殊疑问句式:疑问词(如what) is it that+其它,本句强调的是什么使得从前宏伟的宫殿蜕变的,所以用表示内容的what,选B
【点评】考查主语从句和强调句,本题强调主语从句的引导词。
38.________ is the centre of our planetary system was a difficult concept to grasp in the Middle Ages.
A. It's the sun and not the earth
B. The sun and not the earth
C. Being the sun and not the earth
D. That the sun and not the earth
【答案】 D
【解析】【分析】句意:太阳而不是地球是我们行星系统的中心,这在中世纪是一个很难理解的概念。分析句子可知,整个句子为主系表结构,was为系动词,它之前的都为主语,且主语由句子来充当,句子结构以及句意完整,所以连词代词为that。故选D。
【点评】考查名词性从句,本题涉及that引导的主语从句。
39.______ makes the school proud is ______ more than 90% of the students have been admitted to universities.
A. what; because
B. that; because
C. that; what
D. what; that
【答案】 D
【解析】【分析】句意:让学校骄傲的是,超过90%的学生被重点大学所录取。第一空主语从句中缺少主语,指代事情,故用what;第二空为表语从句,且从句中不缺少成分,故填关系词that。故选D。
【点评】考查名词性从句,本题涉及what引导的主语从句和that引导的表语从句。40.The school library is ________ we can read many books and magazines.
A. what
B. where
C. when
D. which
【答案】 B
【解析】【分析】句意:学校图书馆是我们能够看书看杂志的地方。What(什么),where(哪里),when(什么时候)which(哪一个)。we can read many books and magazines修饰主语,是一个表语从句。图书馆是一个地方,连接词用where。故选B。【点评】考查表语从句的连词。
必修五数列单元测试
必修五数列复习综合练习题 一、选择题(本大题共12小题,每小题5分,共60分,在每小题给出的四个选项中,只有一项是符合题目要求的) 1.2011是等差数列:1,4,7,10,…的第几项( ) (A )669 (B )670 (C )671 (D )672 2.数列{a n }满足a n =4a n-1+3,a 1=0,则此数列的第5项是( ) (A )15 (B )255 (C )20 (D )8 3.等比数列{a n }中,如果a 6=6,a 9=9,那么a 3为( ) (A )4 (B )2 3 (C ) 9 16 (D )2 4.在等差数列{a n }中,a 1+a 3+a 5=105,a 2+a 4+a 6=99,则a 20=( ) (A )-1 (B )1 (C )3 (D )7 5.在等差数列{a n }中,已知a 1=2,a 2+a 3=13,则a 4+a 5+a 6=( ) (A )40 (B )42 (C )43 (D )45 6.记等差数列的前n 项和为S n ,若S 2=4,S 4=20,则该数列的公差d=( ) (A)2 (B)3 (C)6 (D)7 7.等差数列{a n }的公差不为零,首项a 1=1,a 2是a 1和a 5的等比中项,则数列的前10项之和是( ) (A )90 (B )100 (C )145 (D )190 8.在数列{a n }中,a 1=2,2a n+1-2a n =1,则a 101的值为( ) (A )49 (B )50 (C )51 (D )52
9.计算机是将信息转化成二进制数进行处理的,二进制即“逢二进一”,如 (1101)2表示二进制的数,将它转化成十进制的形式是1×23+1×22+0×21+1×20=13,那么将二进制数16111???位 转换成十进制数的形式是( ) (A )217-2 (B )216-1 (C )216-2 (D )215-1 10.在等差数列{a n }中,若a 1+a 2+a 3=32,a 11+a 12+a 13=118,则a 4+a 10=( ) (A )45 (B )50 (C )75 (D )60 11.(2011·江西高考)已知数列{a n }的前n 项和S n 满足:S n +S m =S n+m ,且a 1=1,那么a 10=( ) (A )1 (B )9 (C )10 (D )55 12.等比数列{a n }满足a n >0,n=1,2,…,且a 5·a 2n-5=22n (n ≥3),则当n ≥1时,log 2a 1+log 2a 3+…+log 2a 2n-1=( ) (A )n(2n-1) (B )(n+1)2 (C )n 2 (D )(n-1)2 二、填空题(本大题共4小题,每小题5分,共20分,请把正确的答案填在题中的横线上) 13.等差数列{a n }前m 项的和为30,前2m 项的和为100,则它的前3m 项的和 为______. 14.(2011·广东高考)已知{a n }是递增等比数列,a 2=2,a 4-a 3=4,则此数列的公比q=______. 15.两个等差数列{a n },{b n }, 12n 12n a a a 7n 2 b b b n 3 ++?++= ++?++,则55a b =______. 16.设数列{a n }中,a 1=2,a n+1=a n +n+1,则通项a n =_____.
《数列》单元测试题(含答案)
《数列》单元练习试题 一、选择题 1.已知数列}{n a 的通项公式432--=n n a n (∈n N *),则4a 等于( ) (A)1 (B )2 (C )3 (D )0 2.一个等差数列的第5项等于10,前3项的和等于3,那么( ) (A )它的首项是2-,公差是3 (B)它的首项是2,公差是3- (C )它的首项是3-,公差是2 (D )它的首项是3,公差是2- 3.设等比数列}{n a 的公比2=q ,前n 项和为n S ,则 =24a S ( ) (A )2 (B)4 (C)2 15 (D )217 4.设数列{}n a 是等差数列,且62-=a ,68=a ,n S 是数列{}n a 的前n 项和,则( ) (A)54S S < (B )54S S = (C)56S S < (D )56S S = 5.已知数列}{n a 满足01=a ,133 1+-=+n n n a a a (∈n N*),则=20a ( ) (A)0 (B)3- (C )3 (D) 23 6.等差数列{}n a 的前m 项和为30,前m 2项和为100,则它的前m 3项和为( ) (A)130 (B)170 (C)210 (D)260 7.已知1a ,2a ,…,8a 为各项都大于零的等比数列,公比1≠q ,则( ) (A)5481a a a a +>+ (B )5481a a a a +<+ (C)5481a a a a +=+ (D )81a a +和54a a +的大小关系不能由已知条件确定 8.若一个等差数列前3项的和为34,最后3项的和为146,且所有项的和为390,则这个数 列有( ) (A )13项 (B)12项 (C)11项 (D)10项 9.设}{n a 是由正数组成的等比数列,公比2=q ,且30303212=????a a a a ,那么 30963a a a a ???? 等于( ) (A)210 (B)220 (C)216 (D)215 10.古希腊人常用小石子在沙滩上摆成各种形状来研究数,比如:
2020年数列单元测试卷-含答案
数列单元测试卷 注意事项: 1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分. 2.答题前,考生务必将自己的姓名、准考证号等信息填涂在答卷相应位置. 第Ⅰ卷(选择题) 一.选择题:本大题共12小题,每小题5分,共60分。每小题给出的四个选项中,只有一 项是符合题目要求的. 1.数列3,5,9,17,33,…的通项公式a n等于( ) A.2n B.2n+1 C.2n-1 D.2n+1 2.下列四个数列中,既是无穷数列又是递增数列的是( ) A.1,1 2 , 1 3 , 1 4 ,… B.-1,2,-3,4,… C.-1,-1 2 ,- 1 4 ,- 1 8 ,… D.1,2,3,…,n 3..记等差数列的前n项和为S n,若a1=1/2,S4=20,则该数列的公差d=________.( ) A.2 B.3 C.6 D.7 4.在数列{a n}中,a1=2,2a n+1-2a n=1,则a101的值为( ) A.49 B.50 C.51 D.52 5.等差数列{a n}的公差不为零,首项a1=1,a2是a1和a5的等比中项,则数列的前10项之和是( ) A.90 B.100 C.145 D.190 6.公比为2的等比数列{a n}的各项都是正数,且a3a11=16,则a5=( ) A.1 B.2 C.4 D.8
7.等差数列{a n }中,a 2+a 5+a 8=9,那么关于x 的方程:x 2 +(a 4+a 6)x +10=0( ) A .无实根 B.有两个相等实根 C .有两个不等实根 D .不能确定有无实根 8.已知数列{a n }中,a 3=2,a 7=1,又数列?? ?? ?? 11+a n 是等差数列,则a 11等于( ) A .0 B.12 C.2 3 D .-1 9.等比数列{a n }的通项为a n =2·3 n -1 ,现把每相邻两项之间都插入两个数,构成一个新的 数列{b n },那么162是新数列{b n }的( ) A .第5项 B.第12项 C .第13项 D .第6项 10.设数列{a n }是以2为首项,1为公差的等差数列,{b n }是以1为首项,2为公比的等比 数列,则 A .1 033 B.1 034 C .2 057 D .2 058 11.设n S 为等差数列{}n a 的前n 项和,且28,171==S a .记[]n n a b lg =,其中[]x 表示不超过x 的最大整数,如[]09.0=,[]199lg =.则b 11的值为( ) A.11 B.1 C. 约等于1 D.2 12.我们把1,3,6,10,15,…这些数叫做三角形数,因为这些数目的点可以排成一个正三角形,如下图所示: 则第七个三角形数是( ) A .27 B.28 C .29 D .30
数列的概念单元测试题含答案百度文库
一、数列的概念选择题 1.在数列{}n a 中,12a =,1 1 1n n a a -=-(2n ≥),则8a =( ) A .1- B . 12 C .1 D .2 2.数列{}n a 的通项公式是2 76n a n n =-+,4a =( ) A .2 B .6- C .2- D .1 3.已知数列{} ij a 按如下规律分布(其中i 表示行数,j 表示列数),若2021ij a =,则下列结果正确的是( ) A .13i =,33j = B .19i =,32j = C .32i =,14j = D .33i =,14j = 4.已知数列{}n a ,若()12* N n n n a a a n ++=+∈,则称数列{}n a 为“凸数列”.已知数列{} n b 为“凸数列”,且11b =,22b =-,则数列{}n b 的前2020项和为( ) A .5 B .5- C .0 D .1- 5.在数列{}n a 中,已知11a =,25a =,() * 21n n n a a a n N ++=-∈,则5a 等于( ) A .4- B .5- C .4 D .5 6.已知数列{}n a ,{}n b ,其中11a =,且n a ,1n a +是方程220n n x b x -+=的实数根, 则10b 等于( ) A .24 B .32 C .48 D .64 7.在数列{}n a 中,114a =-,1 11(1)n n a n a -=->,则2019a 的值为( )