2010年真题及答案
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2010年普通高等学校招生全国统一考试(新课标全国卷)文综历史试题24.西周分封制在中国历史上影响深远。
下列省、自治区中,其简称源自西周封国国名的是A.河南、河北B.湖南、湖北C.山东、山西D.广东、广西25.柳宗元在《封建论》中评价秦始皇废封建、行郡县说:“其为制,公之大者也……公天下之端自始皇。
”郡县制为“公天下”之开端,主要体现在A.百姓不再是封君的属民B.更有利于皇帝集权C.制度法令的统一D.依据才干政绩任免官吏26.王安石提出“形者,有生之本”。
与之相对立的观点是A.“心外无物”B.“天地为万物之本”C.“夫形于天地之间也,物也”D.“舍天地则无以为道”27.表2 明代洪武至弘治年间(1368---1505)徽州祁门土地买卖契约情况表表2反映了A.宝钞在民间的信用降低B.社会经济大幅度衰退C.生活资料均可作为支付手段D.白银始终是主要流通货币28.亚里士多德在《政治学》中认为,世上有两种形式的平等,即数量平等和比值平等。
数量平等是绝对平均主义,比值平等则是根据个人的实际价值,按比例分配与之相称的事物。
根据以上观点,通常所说的“分数面前人人平等”应该是A.更接近于数量平等B.更接近于比值平等C.数量平等高于比值平等D.既非数量平等又非比值平等29.图四是英国1782年的一幅漫画。
此漫画反映了A.英国国际地位下降B.英美关系亲近友好C.英国承认美国独立D.英国愿与美国和解30.19世纪中期,许多与西学相关的“日本新词”来自中国,而在20世纪初年,大量与西学相关的“日本新词”,如劳动、方针、政策、理论等迅速传入中国。
出现这一变化的决定性因素是A.中国留学日本人数增多B.中国在甲午战争中战败C.日本明治维新成效显著D.日本先于中国接触西学31.1902—1906年,京师大学堂师范馆只有学生512人,其中举人62人、贡生48人、生员232人、监生84人。
这表明此时A.传统教育制度稳定发展B.新式学堂教育得到普及C.学生以求取功名为目的D.教育制度处于转型时期32.某博物馆收藏的一份传单写道:“彼得格勒城市及郊区的所有工人、水兵、赤卫队和铁路组织的会议……决定,派我们中间的优秀分子加入‘为饥饿的彼得格勒到农村征粮’的队伍。
1. 1984年1月3日,意大利人卡内帕给恩格斯写信,请求他为即将在日内瓦出版的饿《新纪元》周刊的创刊号题词,而且要求尽量用简短的字句来表述未来的社会主义纪元的基本思想,以区别于伟大诗人但丁的对旧纪元所作的“一些人统治,另一些人受苦难”的界定。
恩格斯回答说,这就是:“代替那存在着阶级和阶级对立的资产阶级旧社会的,将是这样一个联合体,在那里,每个人的自由发展是一切人的自由发展的条件。
”这段话表明,马克思主义追求的根本价值目标是()A.实现人的自由而全面的发展B.实现人类永恒不变的普适价值C.建立一个四海之内皆兄弟的大同世界D.建立一个自由,平等,博爱的理性王国【答案】A【解析】本题考查的考点是马克思主义最崇高的社会理想,即马克思追求的根本价值目标,进入共产主义社会,实现人的自由而全面的发展,所以,正确答案是A选项。
2.有一则箴言:“在溪水和岩石的斗争中,胜利的总是溪水,不是因为力量,而是因为坚持。
”“坚持就是胜利”的哲理在于()A.必然性通过偶然性开辟道路B.肯定中包含着否定的因素C.量变必然引起质变D.有其因必有其果【答案】C【解析】坚持就是胜利,体现了事物量变发展到一定阶段必然会引起质变,达到事物根本性质的变化,所以,本题体现的是量变必然引起质变,正确答案是选项C。
3. 右边这张照片反映出由于气候变暖,北极冰盖融化,致使北极熊无处可去的场景,颇具震撼力。
它给我们地球上的人类发出的警示是()A.人与自然的关系成为人与人之间一切社会关系的核心B.生态失衡已成为自然界自身周期演化不可逆转的趋势C.自然地理环境已成为人类社会发展的根本决定力量D.生态环境已日益成为人类反思自身活动的重要前提【答案】D【解析】本题考查人与自然的关系,气候变暖给人类发出的警示是人在对于自然的作用过程中,生态环境已日益成为人类反思自身活动的重要前提,保护自然,协调人和自然的关系是大势所趋,所以,正确答案是选项D。
4. 劳动力成为商品是货币转化为资本的前提条件,这是因为()A.资本家购买的是劳动力的价值B.劳动力商品具有价值和使用价值C.货币所有者购买的劳动力能够带来剩余价值D.劳动力自身的价值能够在消费过程中转移到新的商品中去【答案】C【解析】劳动力商品的最主要特点,表现在它的使用价值上。
2010司法考试真题一、单项选择题。
每题所设选项中只有一个正确答案,多选、错选或不选均不得分。
本部分含1—50题,每题1分,共50分。
1.司法公正是司法工作的灵魂,是依法治国的重要标志。
社会主义法治理念要求司法机关必须“严格公正司法”。
下列哪一选项不符合社会主义法治理念的精神和要求?A.司法机关必须坚持实体公正和程序公正相结合,做到法律效果、政治效果和社会效果相统一B.司法机关必须进一步提高办案效率,坚持公正与效率兼顾C.司法机关为了保障判决有效执行,应对当事人实行“一站式服务”,即谁立案谁审判谁执行D.司法机关为了加强审判监督,可主动邀请人大代表、政协委员和新闻媒体旁听重大疑难案件审判2.为了落实司法便民,检察院开设了网上举报、申诉和信息查询系统,法院实现网上预约立案和电子签章,公民对国家机关实行网上监督收效明显。
关于网络技术在法治建设中的作用,下列哪一选项是不正确的?A.社会主义法治理念的落实要与现代科学技术的发展相结合B.社会主义法治理念的落实也体现于对网络依法进行管理C.司法机关是否贯彻社会主义法治理念,其衡量的根本指标即是否采用现代科技手段D.司法机关采用网络技术落实司法便民,是在工作中做到执法为民的具体表现3.社会主义法治理念的核心内容是“依法治国”。
关于“依法治国”,下列哪一选项是错误的?A.依法治国以国家法律体系的健全、完善、规范、系统、协调为必要条件B.依法治国依赖于法制完备,法律健全完备了,法治就实现了C.依法治国应当树立宪法法律的权威D.依法治国的实现,必须以规范和制约公权力为前提,做到职权法定、有权必有责、用权受监督、违法受追究4.执法为民是社会主义法治的本质要求。
对此,下列哪一选项是不正确的?A.执法为民要求尊重和保障人权,这是宪法规定的一项基本原则B.执法为民强调以人为本,这是科学发展观的核心C.执法为民表明执法机关存在的目的在于合法地行使人民赋予的权力D.执法为民说明执法活动以“及时”、“高效”作为最根本的出发点5.关于社会主义法治理念及其特征的表述,下列哪一选项是错误的?A.社会主义法治理念重在强调行政执法和司法工作应遵守一定的原则,与立法没有直接关系B.社会主义法治理念反映和坚持了人民民主专政的国体C.社会主义法治理念反映了社会主义法治的性质、功能、价值取向和实现途径D.社会主义法治理念中的法治建设根本目标是实现好、维护好、发展好最广大人民的利益6.法律格言说:“不知自己之权利,即不知法律。
▲2010年普通高等学校招生全国统一考试(安徽卷)数 学(文科)本试卷分第I 卷(选择题)和第II 卷(非选择题)两部分,第Ⅰ卷第1页至第2页,第Ⅱ卷第3页至第4页.满分150分.考试用时120分钟.参考公式:S 表示底面积,h 表示底面上的高 如果事件A 与B 互斥,那么 棱柱体积 Sh V = )()()(B P A P B A P +=+ 棱锥体积 Sh V 31=第Ⅰ卷(选择题 共50分)一、选择题:本大题共10小题,每小题5分,共50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)若}03|{},01|{<-=>+=x x B x x A ,则A ∩B=(A )(-1,+∞)(B )(-∞,3)(C )(-1,3)(D )(1,3)(2)已知12-=i ,则=-)31(i i(A )i -3 (B )i +3 (C )i --3 (D )i +-3(3)设向量)21,21(),0,1(==b a ,则下列结论中正确的是(A )||||b a = (B )22=⋅b a (C )b a // (D )b a -与b 垂直(4)过点(1,0)且与直线022=--y x 平行的直线方程是 (A )012=--y x (B )012=+-y x(C )022=-+y x(D )012=-+y x(5)设数列}{n a 的前n 项和2n S n =,则8a 的值为(A )15(B )16(C )49 (D )64(6)设0>abc ,二次函数c bx ax x f ++=2)(的图象可能是(7)设,)52(,)52(,)53(525352===c b a 则a ,b ,c 的大小关系是(A )b c a >> (B )c b a >>(C )b a c >>(D )a c b >>(8)设y x ,满足约束条件⎪⎩⎪⎨⎧≥≤-+≥-+,0,062,062y y x y x 则目标函数y x z +=的最大值是(A )3(B )4(C )6(D )8▲▲(9)一个几何全体的三视图如图,该几何体的表面积为(A )372(B )360(C )292(D )280▲▲(10)甲从正方形四个顶点中任意选择两个顶点连成直线,乙也从该正方形四个顶点中任意选择两个顶点连成直线,则所得的两条直线相互垂直的概率是(A )183 (B )184 (C )185 (D )186二、填空题;本大题共5小题,每小题5分,共25分。
2010年普通高等学校招生全国统一考试(新课标卷)化学试题第I卷一、选择题(共42分)7.下列各项表达中正确的是( )A.Na2O2的电子式为B.106g的乙醇和丙醇混合液完全燃烧生成的CO2为112L(标准状况)C.在氮原子中,质子数为7而中子数不一定为7D.Cl-的结构示意图为8.分子式为C3H6Cl2的同分异构体共有(不考虑立体异构)( )A.3种 B.4种 C.5种 D.6种9.下列各组中的反应,属于同一反应类型的是( )A.由溴丙烷水解制丙醇;由丙烯与水反应制丙醇B.由甲苯硝化制对硝基甲苯;由甲苯氧化制苯甲酸C.由氯代环己烷消去制环己烯;由丙烯加溴制1,2-二溴丙烷D.由乙酸和乙醇制乙酸乙酯;由苯甲酸乙酯水解制苯甲酸和乙醇10.把500mL有BaCl2和KCl的混合溶液分成5等份,取一份加入含a mol硫酸钠的溶液,恰好使钡离子完全沉淀;另取一份加入含b mol硝酸银的溶液,恰好使氯离子完全沉淀。
则该混合溶液中钾离子浓度为( )A.0.1(b-2a) mol/L B.10(2a-b) mol/LC.10(b-a) mol/L D.10(b-2a) mol/L11.己知:HCN(aq)与NaOH(aq)反应的∆H = -12.1 kJ/mol;HCl(aq)与NaOH(aq)反应的∆H = -55.6 kJ/mol。
则HCN在水溶液中电离的∆H等于( )A.-67.7 kJ/mol B.-43.5 kJ/molC.+43.5 kJ/mol D.+67.7 kJ/mol12.根据右图,可判断出下列离子方程式中错误的是( )A.2Ag(s)+Cd2+(aq)==2Ag+(aq)+Cd(s)B.Co2+(aq)+Cd(s)==Co(s)+Cd2+(aq)C.2Ag+(aq)+Cd(s)==2Ag(s)+Cd2+(aq)D. 2Ag+(aq)+Co(s)==2Ag(s)+Co2+(aq)13.下表中评价合理的是( )选项化学反应及其离子方程式评价A Fe3O4与稀硝酸反应:2Fe3O4+18H+=6Fe3++H2↑+8H2O 正确B 向碳酸镁中加入稀盐酸: CO32-+2H+==CO2+ H2O 错误,碳酸镁不应该写成离子形式C 向硫酸铵溶液中加入氢氧化钡溶液:Ba2++SO42-==BaSO4↓正确D FeBr2溶液与等物质的量的Cl2反应:2Fe2++2Br-+2Cl2==2Fe3++4Cl-+Br2错误,Fe2+与Br-的化学计量数之比应为1:2第Ⅱ卷必考:二、非选择题(共43分)26.(14分)物质A~G有下图所示转化关系(部分反应物、生成物没有列出)。
2010考研数学(一)真题及参考答案一、选择题(1)、极限2lim ()()x x x x a x b ®¥æö=ç÷-+èø( C ) A 、1 B 、e C 、a be - D 、b ae-【详解】【详解】()()2222ln 1()()()()()()()()lim lim lim ()()lim lim xx x x x x a x b x a x b x x x a b x ab a b x abxx x a x b x a x b x x a bx e e x a x b ee eæöæö-ç÷ç÷ç÷ç÷-+-+èøèø®¥®¥®¥-+æö-+ç÷ç÷-+-+èø®¥®¥-æö==ç÷-+èø===(2)、设函数(,)z z x y =,由方程(,)0y z F x x =确定,其中F 为可微函数,且20F ¢¹,则z zx y u y¶¶+=¶¶( B )A 、xB 、zC 、x -D z -【详解】【详解】 等式两边求全微分得:121212()()()0x x y y z z Fu F v dx Fu F v dy Fu F v dz ¢¢¢¢¢¢+++++=, 所以有,1212x x z z F u F v z x F u F v ¢¢+¶=-¢¢¶+,1212yy z z Fu F v z y Fu F v ¢¢+¶=-¢¢¶+, 其中,2x y u x =-,1y u x =,0z u =,2x z v x =-,0yv =,1z v x=,代入即可。
2010年考研英语真题与答案解析从2010年开始,全国硕士研究生入学考试的英语试卷分为了英语(一)和英语(二)。
英语(一)即原统考“英语”。
英语(二)主要是为高等院校和科研院所招收专业学位硕士研究生而设置的具有选拔性质的统考科目。
英语一考试形式、考试内容与试卷结构(一)考试形式考试形式为笔试。
考试时间为180分钟。
满分为100分。
试卷包括试题册和答题卡。
答题卡分为答题卡1和答题卡2。
考生应将1~45题的答案按要求填涂在答题卡1上,将46~52题的答案写在答题卡2上。
(二)考试内容试题分三部分,共52题,包括英语知识运用、阅读理解和写作。
第一部分英语知识运用该部分不仅考查考生对不同语境中规范的语言要素(包括词汇、表达方式和结构)的掌握程度,而且还考查考生对语段特征(如连贯性和一致性等)的辨识能力等。
共20小题,每小题0.5分,共10分。
在一篇240~280词的文章中留出20个空白,要求考生从每题给出的4个选项中选出最佳答案,使补全后的文章意思通顺、前后连贯、结构完整。
考生在答题卡1上作答。
第二部分阅读理解该部分由A、B、C三节组成,考查考生理解书面英语的能力。
共30小题,每小题2分,共60分。
A节(20小题):主要考查考生理解主旨要义、具体信息、概念性含义,进行有关的判断、推理和引申,根据上下文推测生词的词义等能力。
要求考生根据所提供的4篇(总长度约为1600词)文章的内容,从每题所给出的4个选项中选出最佳答案。
考生在答题卡1上作答。
B节(5小题):主要考查考生对诸如连贯性、一致性等语段特征以及文章结构的理解。
本部分有3种备选题型。
每次考试从这3种备选题型中选择一种进行考查。
考生在答题卡1上作答。
备选题型有:1)本部分的内容是一篇总长度为500~600词的文章,其中有5段空白,文章后有6~7段文字。
要求考生根据文章内容从这6~7段文字中选择能分别放进文章中5个空白处的5段。
2)在一篇长度约500~600词的文章中,各段落的原有顺序已被打乱,要求考生根据文章的内容和结构将所列段落(7~8个)重新排序,其中有2~3个段落在文章中的位置已给出。
2010年考研英语真题及答案一、考研英语真题(阅读理解部分)1.Passage 1文章摘自《纽约时报》(The New York Times),讲述了人们对于沙特阿拉伯的德里布(Dariba)地区商业开发的反对声浪。
作者主要介绍了沙特人对这个开发计划的局部有效性提出了质疑。
答案:D解析:根据文章内容可以推断出,该地区商业发展项目在解决当地人就业问题以及对年轻人带来激励方面并不有效。
所以答案为D。
2.Passage 2文章介绍了爬行动物的生态类型和生存对策。
通过对几种不同爬行动物的研究和观察,作者总结了它们对环境的适应能力和繁衍生息策略。
答案:C解析:根据文章内容可以得出,某些种类的爬行动物具有在生境发生变化时进行数量调整的能力。
所以答案为C。
3.Passage 3文章介绍了一种新的种植模式,旨在减少对水资源的需求以及提高产量。
作者通过对这种种植模式的实验研究,发现它可以在干旱地区获得较高的产量。
答案:B解析:根据文章内容可以得出,这种新的种植模式通过改变作物的生长方式,减少了对水资源的需求,从而提高了产量。
所以答案为B。
二、答案解析1.Passage 1题目要求解释为什么该地区商业发展项目在解决当地人就业问题方面并不有效。
文章中提到该开发项目只提供了少量工作岗位,远远不够满足就业需求。
所以答案为D。
2.Passage 2题目要求解释某些爬行动物的数量调整能力。
通过文章可以看出,某些爬行动物能够根据其所处环境的变化来调整自身的数量,以适应变化的生境条件。
所以答案为C。
3.Passage 3题目要求解释这种新的种植模式在干旱地区获得高产量的原因。
文章中解释了这种新的种植模式通过改变作物的生长方式,减少了对水资源的需求,从而提高了产量。
所以答案为B。
三、总结本篇文章简要介绍了2010年考研英语阅读理解部分的三篇真题及其答案解析。
通过阅读这些真题及答案解析,可以帮助考生了解考研英语阅读理解题型和解题思路,提高解题能力。
2010年考研英语(一)真题及答案解析2010年考研英语(一)真题及答案解析2010年考研英语(一)真题及答案解析Section I Use of EnglishDirections:Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on the ANSWER SHEET. (10 points)The idea that hard work is the key to success is nothing new.1,_____new research from psychologist Anders Ericsson and 2_____ colleagues suggests that practice is the magic number of greatness.Ericsson studies thousands of chess players, musicians, athletes and others. He 3_____ out the average number of training hours per week the people he studied 4_____ in _____ to reach world-class levels of performance. Across the board, 5_____ to the 10 years or 10,000 hours were required. 6_____, more recent research_____ out that the amount of practice time needed may vary in fields that____ many social or physical activities. 7_____, deliberate practice is the key ingredient for achieving______ results in any field.Deliberate practice is not just mindless repetition. It is a purposeful and thoughtful 8_____ that requires intense focus. 9_____have discovered that top performers spend less time in _____ practice compared to average performers, but their practice is so much more productive. They grow_____, receive constant feedback and continually 10_____ their performance.Achieving world-class performance, according to Ericsson, is not about talent or innate ability; it is all about deliberate practice.1. [A] But[B] Or [C] So [D] Yet2. [A] their[B] his [C] other [D] the3. [A] found [B] turned[C] checked[D] carried4. [A] took part [B] trained [C] relied [D] engaged5. [A] up to [B] for [C] in addition [D] by far6. [A] Consequently [B] Importantly[C] Additionally[D] Meanwhile7. [A] Although [B] Besides[C] However[D] Therefore8. [A] future[B] experience [C] exercise [D] performance9. [A] Workers [B] Researchers [C] Engineers [D] Scientists10. [A] evaluate[B] develop [C] explain [D] demonstrate解析:1. [A] But 是转折连词,与"hard work is the key to success"对立,而下文要说明practice才是成功的关键,所以应该选[A] But。
(2) B 【解析】由a+2i=b+i i得a+2i=bi-1,所以由复数相等的意义知a=-1,b=2,所以a+b=1,故选B.【命题意图】本题考查复数相等的意义、复数的基本运算,属保分题。
(3)D 【解析】由空间直线与平面的位置关系及线面垂直与平行的判定与性质定理可以得出答案。
【命题意图】考查空间直线与平面的位置关系及线面垂直与平行的判定与性质,属基础题。
(4)【答案】D(7) A 【解析】由题意得:所求封闭图形的面积为1230x -x )dx=⎰(1111-1=3412⨯⨯,故选A 。
【命题意图】本题考查定积分的基础知识,由定积分求曲线围成封闭图形的面积。
可知当直线z=3x-4y平移到点(5,3)时,目标函数z=3x-4y取得最大值3;当直线z=3x-4y 平移到点(3,5)时,目标函数z=3x-4y取得最小值-11,故选A。
【命题意图】本题考查不等式中的线性规划知识,画出平面区域与正确理解目标函数z=3x-4y的几何意义是解答好本题的关键。
(11)函数y=2x-2x的图像大致是A 【解析】因为当x=2或4时,2x -2x =0,所以排除B 、C ;当x=-2时,2x -2x =14<04-,排除D ,所以选A 。
【命题意图】本题考查函数的图象,考查同学们对函数基础知识的把握程度以及数形结合的思维能力。
12 B 【解析】若a 与b共线,则有a b=mq-np=0,故A 正确;因为b a pn-qm = ,而a b=mq-np,所以有a b b a ≠,故选项B 错误,故选B 。
【命题意图】本题在平面向量的基础上,加以创新,属创新题型,考查平面向量的基础知识以及分析问题、解决问题的能力。
二【答案】54-【解析】当x=10时,y=110-1=42⨯,此时|y-x|=6; 当x=4时,y=14-1=12⨯,此时|y-x|=3;当x=1时,y=111-1=-22⨯,此时|y-x|=32;当x=12-时,y=115-1=-224⨯-(),此时|y-x|=3<14,故输出y 的值为54-。
2010年普通高等学校招生全国统一考试(全国Ⅰ卷)英语试题第一部分听力(共两节,满分30分)第一节(共5小题:每小题1.5分,满分7.5分)听下面5段对话。
每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳答案,并标在试卷的相应位置。
听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
例:How much is the shirt?A.$ 19.15B. $9.15C. $ 9.18答案是B1.What will Dorothy do on the weeked?A.go out with her friendB.work on her paperC.make some plans2.What was the normal price of the T-shirt ?A.$15B. $ 30C. $503.What has the woman decided to do on Sunday afternoon?A.to attend a wedding.B.To visit an exhibitionC.To meet a friend4.When does the bank close on Sunday ?A.at 1:00pmB.at 3:00pmC.at 4:00pm5.Where are the speakers?A.In a storeB.In a classroomC.At a hotel第二节(共15小题;每小题1.5分,满分22.5分)听下面5段对话或独白。
每段对话或独白后有几小题,从题中所给的A、B、C 三个选项中选出最佳答案,并标在试卷的相应位置。
听完每段对话后,你将有时间阅读各小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。
每段对话或独白读两遍。
听第6段材料,回答第6,7 小题6,What do we know about Nora?A.She prefers a room of her own.B.She likes to work with other girls.C.She lives near the city center.7.What is good about the flat?A. It has a large sitting room.B. It has good furnitureC. It has a big kitchen.听第7 段材料,回答第8,9题。
2010年全国硕士研究生入学统一考试数学一试题一、选择题(1~8小题,每小题4分,共32分.下列每题给出的四个选项中,只有一个选项符合题目要求的,请将所选项前的字母填在答题纸...指定位置上.) (1) 极限2lim ()()xx x x a x b →∞⎡⎤=⎢⎥-+⎣⎦( ) (A) 1. (B) e . (C) a be -. (D) b ae-.(2) 设函数(,)z z x y =,由方程,0y z F x x ⎛⎫=⎪⎝⎭确定,其中F 为可微函数,且20F '≠,则z zxy x y∂∂+=∂∂( ) (A) x . (B) z . (C) x -. (D) z -.(3) 设,m n 是正整数,则反常积分⎰的收敛性 ( )(A) 仅与m 的取值有关. (B)仅与n 的取值有关. (C) 与,m n 取值都有关. (D) 与,m n 取值都无关. (4) ()()2211limn nn i j nn i n j →∞===++∑∑ ( ) (A)()()120111xdx dy x y ++⎰⎰. (B) ()()100111x dx dy x y ++⎰⎰. (C)()()11111dx dy x y ++⎰⎰. (D) ()()1120111dx dy x y ++⎰⎰. (5) 设A 为m n ⨯矩阵,B 为n m ⨯矩阵,E 为m 阶单位矩阵,若AB E =,则 ( )(A) 秩()r A m =,秩()r B m =. (B) 秩()r A m =,秩()r B n =. (C) 秩()r A n =,秩()r B m =. (D) 秩()r A n =,秩()r B n =. (6) 设A 为4阶实对称矩阵,且2A A O +=,若A 的秩为3,则A 相似于 ( )(A) 1110⎛⎫ ⎪ ⎪ ⎪ ⎪⎝⎭. (B) 1110⎛⎫ ⎪⎪ ⎪- ⎪⎝⎭.(C) 1110⎛⎫ ⎪- ⎪ ⎪- ⎪⎝⎭. (D) 1110-⎛⎫ ⎪- ⎪ ⎪- ⎪⎝⎭. (7) 设随机变量X 的分布函数0,1(),0121,1x x F x x e x -<⎧⎪⎪=≤<⎨⎪-≥⎪⎩,则{}1P X == ( ) (A) 0. (B)12. (C) 112e --. (D) 11e --. (8) 设1()f x 为标准正态分布的概率密度,2()f x 为[]1,3-上均匀分布的概率密度,若12(),0()(),0af x x f x bf x x ≤⎧=⎨>⎩,(0,0)a b >>为概率密度,则,a b 应满足 ( ) (A) 234a b +=. (B) 324a b +=. (C) 1a b +=. (D) 2a b +=.二、填空题(9 14小题,每小题4分,共24分.请将答案写在答题纸...指定位置上.) (9) 设()20,ln 1,t tx e y u du -⎧=⎪⎨=+⎪⎩⎰ 求220t d y dx == .(10)2π=⎰.(11) 已知曲线L 的方程为[]{}11,1y x x =- ∈-,起点是()1.0-,终点是()1,0,则曲线积分2Lxydx x dy +=⎰.(12) 设(){}22,,1x y z xy z Ω=+≤≤,则Ω的形心的竖坐标z = .(13) 设()()()1231,2,1,0,1,1,0,2,2,1,1,TTTa ααα=-==,若由123,,ααα生成的向量空间的维数是2,则a = .(14) 设随机变量X 的概率分布为{}!C P X k k ==,0,1,2,k = ,则()2E X = .三、解答题(15~23小题,共94分.请将解答写在答题纸...指定位置上.解答应写出文字说明、证明过程或演算步骤.)求微分方程322x y y y xe '''-+=的通解. (16)(本题满分10分)求函数()()2221x t f x xt e dt -=-⎰的单调区间与极值.(17)(本题满分10分)(I)比较()1ln ln 1n t t dt +⎡⎤⎣⎦⎰与10ln nt t dt ⎰()1,2,n = 的大小,说明理由;(II)记()1ln ln 1nn u t t dt =+⎡⎤⎣⎦⎰()1,2,n = ,求极限lim n n u →∞. (18)(本题满分10分)求幂级数()121121n n n x n -∞=--∑的收敛域及和函数.(19)(本题满分10分)设P 为椭球面222:1S x y z yz ++-=上的动点,若S 在点P 处的切平面与xOy 面垂直,求点P 的轨迹C ,并计算曲面积分2x y zI ∑-=,其中∑是椭球面S 位于曲线C 上方的部分.(20)(本题满分11分)设110111a A b λλλ ⎛⎫⎛⎫ ⎪ ⎪= - 0= ⎪ ⎪ ⎪ ⎪1 1 ⎝⎭⎝⎭,,已知线性方程组Ax b =存在两个不同的解.( I ) 求λ,a ;( II ) 求方程组Ax b =的通解. (21)(本题满分11 分)已知二次型123(,,)T f x x x x Ax =在正交变换x Qy =下的标准形为2212y y +,且Q 的第三列为T. ( I ) 求矩阵A ;( II ) 证明A E +为正定矩阵,其中E 为3阶单位矩阵. (22)(本题满分11分)设二维随机变量(,)X Y 的概率密度为2222(,)x xy y f x y Ae -+-=,x -∞<<+∞,y -∞<<+∞,求常数A 及条件概率密度|(|)Y X f y x .设总体X其中参数()0,1θ∈未知,以i N 表示来自总体X 的简单随机样本(样本容量为n )中等于i 的个数(1,2,3i =).试求常数123,,a a a ,使31iii T a N ==∑为θ的无偏估计量,并求T 的方差.2010年全国硕士研究生入学统一考试数学一试题参考答案一、选择题(1)【答案】 (C).【解析】本题属于未定式求极限,极限为1∞型,故可以用“e 的抬起法”求解.()()2lim xx x x a x b →∞⎡⎤⎢⎥-+⎣⎦()()2lnlim x x x a x b x e ⋅-+→∞=()()2lim lnx x x x a x b e→∞⋅-+=,其中又因为()()2222()()lim ln lim ln 1()()()()lim()()()lim()()x x x x x x x a x b x x x a x b x a x b x x x a x b x a x b a b x abxx a x b a b→∞→∞→∞→∞--+⋅=+-+-+⎡⎤--+⎣⎦=-+-+=-+=-⎡⎤⎣⎦故原式极限为a be-,所以应该选择(C).(2)【答案】 (B).【解析】122212122221x z y z y zF F F F F yF zF zx x x x x F F xF F x⎛⎫⎛⎫''''-+-⋅+⋅ ⎪ ⎪'''+∂⎝⎭⎝⎭=-=-==∂''''⋅, 112211y z F F F z x y F F F x'⋅''∂=-=-=-∂'''⋅, 1212222yF zF yF F z z z xy z x y F F F ''''+⋅∂∂+=-==∂∂'''. (3) 【答案】 (D).【解析】0x =与1x =都是瑕点.应分成dx dx =+⎰,用比较判别法的极限形式,对于,由于121012[ln (1)]lim 11mnx n mx xx+→--=.显然,当1201n m<-<,则该反常积分收敛. 当120n m -≤,1210[ln (1)]lim mx nx x+→-存在,此时实际上不是反常积分,故收敛.故不论,m n 是什么正整数,总收敛.对于,取01δ<<,不论,m n 是什么正整数,121211[ln (1)]lim lim ln (1)(1)01(1)mnmx x x xx x x δδ--→→-=--=-,所以收敛,故选(D).(4)【答案】 (D). 【解析】()()222211111()nnnn i j i j n nn i n j n i n j =====++++∑∑∑∑22111()()n n j i n n j n i ===++∑∑ 12220211111lim lim ,11()nn n n j j n dy j n jn y n→∞→∞====+++∑∑⎰ 1011111lim lim ,11()nn n n i i n dx i n i n x n→∞→∞====+++∑∑⎰()()2222111111lim lim()()n nn nn n i j j i n n j n i n i n j →∞→∞=====++++∑∑∑∑ 221(lim )nn j n n j→∞==+∑1(lim )nn i nn i →∞=+∑1120011()()11dx dy x y =++⎰⎰()()11200111dx dy x y =++⎰⎰. (5)【答案】 (A).【解析】由于AB E =,故()()r AB r E m ==.又由于()(),()()r AB r A r AB r B ≤≤,故(),()m r A m r B ≤≤ ①由于A 为m n ⨯矩阵,B 为n m ⨯矩阵,故(),()r A m r B m ≤≤ ②由①、②可得(),()r A m r B m ==,故选A. (6)【答案】 (D).【解析】设λ为A 的特征值,由于2A A O +=,所以20λλ+=,即(1)0λλ+=,这样A 的特征值只能为-1或0. 由于A 为实对称矩阵,故A 可相似对角化,即A Λ ,()()3r A r =Λ=,因此,1110-⎛⎫ ⎪- ⎪Λ= ⎪- ⎪⎝⎭,即1110A -⎛⎫⎪- ⎪Λ= ⎪- ⎪⎝⎭. (7) 【答案】 (C).【解析】离散型随机变量的分布函数是跳跃的阶梯形分段函数,连续型随机变量的分布函数是连续函数.观察本题中()F x 的形式,得到随机变量X 既不是离散型随机变量,也不是连续型随机变量,所以求随机变量在一点处的概率,只能利用分布函数的定义.根据分布函数的定义,函数在某一点的概率可以写成两个区间内概率的差,即{}{}{}()()1111111110122P X P X P X F F e e --==≤-<=--=--=-,故本题选(C).(8)【答案】 (A).【解析】根据题意知,()221x f x e -=(x -∞<<+∞),()21,1340,x f x ⎧ -≤≤⎪=⎨⎪ ⎩其它利用概率密度的性质:()1f x dx +∞-∞=⎰,故()()()()03121001312424a a f x dx af x dx bf x dx f x dxb dx b +∞+∞+∞-∞-∞-∞=+=+=+=⎰⎰⎰⎰⎰ 所以整理得到234a b +=,故本题应选(A).二、填空题 (9) 【答案】0.【解析】因为 ()()22ln 1ln 1tttdy t e dx e -+==-+-,()()()()22222ln 12ln 11tt t td te d y dt t e t e e dx dt dx t -+⎡⎤=⋅=-⋅-+⋅-⎢⎥+⎣⎦,所以220t d y dx ==. (10)【答案】 4π-.t =,2x t =,2dx tdt =,利用分部积分法, 原式220cos 22cos 2sin t t tdt t tdt t d t πππ=⋅==⎰⎰⎰20002sin 2sin 4cos t t t tdt td t πππ⎡⎤=-=⎢⎥⎣⎦⎰⎰0004cos cos 4cos 4sin 4t t tdt t ππππππ⎡⎤=-=-=-⎢⎥⎣⎦⎰.(11) 【答案】0.【解析】12222LL L xydx x dy xydx x dy xydx x dy +=+++⎰⎰⎰()()()01221011x x dx x dx x x dx x dx -=+++-+-⎰⎰()()0122122xx dx x x dx -=++-⎰⎰1322310223223x x x x -⎛⎫⎛⎫=++- ⎪ ⎪⎝⎭⎝⎭211203223⎛⎫⎛⎫=--++-= ⎪ ⎪⎝⎭⎝⎭(12) 【答案】23. 【解析】 ()2221221211000211212021r rrz d rdr zdxdydz d rdr zdz dxdydz d rdr dz d r rdrππππθθθθΩΩ⎛⎫⎪⋅ ⎪⎝⎭==-⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰⎰4211222r d r dr πθπ⎛⎫-⎪⎝⎭=⎰⎰126204122r r d πθπ⎛⎫- ⎪⎝⎭=⎰20112266322d πθπππ⋅===⎰.(13)【答案】6a =.【解析】因为由123,,ααα生成的向量空间维数为2,所以123(,,)2r ααα=. 对123(,,)ααα进行初等行变换:123112112112211013013(,,)1010130060202000a a a ααα⎛⎫⎛⎫⎛⎫⎪ ⎪ ⎪-- ⎪ ⎪ ⎪=→→ ⎪ ⎪ ⎪-- ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭所以6a =.(14) 【答案】2.【解析】利用离散型随机变量概率分布的性质,知{}001!k k CP X k Ce k ∞∞======∑∑,整理得到1C e -=,即 {}111!!k e P X k e k k --===.故X 服从参数为1的泊松分布,则()()1,1E X D X ==,根据方差的计算公式有()()()222112E X D X E X =+=+=⎡⎤⎣⎦.三、解答题(15)【解析】对应齐次方程的特征方程为2320λλ-+=,解得特征根121,2λλ==,所以对应齐次方程的通解为212x x c y C e C e =+.设原方程的一个特解为*()x y x ax b e =+,则()()*22x y axax bx b e '=+++,()()*2422x y axax bx a b e ''=++++,代入原方程,解得1,2a b =-=-,故特解为*(2)xy x x e =--. 故方程的通解为*212(2)x xx c y y y C e C e x x e =+=+-+.(16)【解析】因为22222222111()()x x x t t t f x x t e dt xe dt te dt ---=-=-⎰⎰⎰,所以2224423311()2222x x t x x t f x x e dt x ex ex e dt----'=+-=⎰⎰,令()0f x '=,则0,1x x ==±.又22421()24x t x f x e dt x e --''=+⎰,则21(0)20t f e dt -''=<⎰,所以2211111(0)(0)(1)22tt f t e dt e e ---=-=-=-⎰是极大值.而1(1)40f e -''±=>,所以(1)0f ±=为极小值.又因为当1x ≥时,()0f x '>;01x ≤<时,()0f x '<;10x -≤<时,()0f x '>;1x <-时,()0f x '<,所以()f x 的单调递减区间为(,1)(0,1)-∞- ,()f x 的单调递增区间为(1,0)(1,)-+∞ .(17)【解析】 (I)当01x <<时0ln(1)x x <+<,故[]ln(1)nnt t +<,所以[]ln ln(1)ln nn t t t t +<,则[]11ln ln(1)ln nn t t dt t t dt +<⎰⎰()1,2,n = .(II)()111101ln ln ln 1n n n t t dt t t dt td t n +=-⋅=-+⎰⎰⎰ ()211n =+,故由 ()1210ln 1n n u t t dt n <<=+⎰,根据夹逼定理得()210lim lim01n n n u n →∞→∞≤≤=+,所以lim 0n n u →∞=.(18)【解析】(I) (1)1222(1)1122(1)(1)2(1)121lim lim (1)(1)2121n n n n n n n n n nx x n n xx n n +-++--→∞→∞--⋅+-+=--⋅--222(21)21lim lim 2121n n n x n x x n n →∞→∞--==⋅=++, 所以,当21x <,即11x -<<时,原级数绝对收敛.当21x >时,原级数发散,因此幂级数的收敛半径1R =.当1x =±时,11211(1)(1)2121n n n n n x n n --∞∞==--⋅=--∑∑,由莱布尼兹判别法知,此级数收敛,故原级数的收敛域为[]1,1-.(II) 设1122111(1)(1)()2121n n nn n n S x x x x n n --∞∞-==⎛⎫--=⋅=⋅⋅ ⎪--⎝⎭∑∑,其中令12111(1)()21n n n S x x n -∞-=-=⋅-∑()1,1x ∈-,所以有 12221111()(1)()n n n n n S x xx ∞∞---=='=-⋅=-∑∑ ()1,1x ∈-,从而有 12211()1()1S x x x '==--+ ()1,1x ∈-, 故 11201()(0)arctan 1xS x dx S x x =+=+⎰,()1,1x ∈-.1()S x 在1,1x =-上是连续的,所以()S x 在收敛域[]1,1-上是连续的.所以()arctan S x x x =⋅,[]1,1x ∈-.(19)【解析】 ( I )令()222,,1F x y z x y z yz =++--,故动点(),,P x y z 的切平面的法向量为()2,2,2x y z zy --,由切平面垂直xOy ,故所求曲线C 的方程为222120x y z yz z y ⎧++-=⎨-=⎩. ( II ) 由⎩⎨⎧=-=-++,02,1222y z yz z y x 消去z ,可得曲线C 在xOy 平面上的投影曲线所围成的xOy 上的区域223:{(,)|1}4D x y x y +≤,由()()x x yz z y x '='-++1222,由dxdy zy yzz y dxdy y z x z dS 24412222--++=⎪⎪⎭⎫⎝⎛∂∂+⎪⎭⎫ ⎝⎛∂∂+=,故(2DDDx y zI x dxdy xdxdy ∑-==+=+⎰⎰⎰⎰⎰⎰12Dπ==⋅=. (20)【解析】因为方程组有两个不同的解,所以可以判断方程组增广矩阵的秩小于3,进而可以通过秩的关系求解方程组中未知参数,有以下两种方法.方法1:( I )已知Ax b =有2个不同的解,故()()3r A r A =<,对增广矩阵进行初等行变换,得111110101010111111a A a λλλλλλ⎛⎫⎛⎫⎪⎪=-→- ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭22111111010101010110011a a λλλλλλλλλ⎛⎫⎛⎫⎪⎪→-→- ⎪ ⎪ ⎪ ⎪-----+⎝⎭⎝⎭ 当1λ=时,11111111000100010000000A a ⎛⎫⎛⎫⎪ ⎪→→ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭,此时,()()r A r A ≠,故Ax b =无解(舍去).当1λ=-时,111102010002A a -⎛⎫ ⎪→- ⎪ ⎪+⎝⎭,由于()()3r A r A =<,所以2a =-,故1λ=- ,2a =-. 方法2:已知Ax b =有2个不同的解,故()()3r A r A =<,因此0A =,即211010(1)(1)011A λλλλλ=-=-+=,知1λ=或-1.当1λ=时,()1()2r A r A =≠=,此时,Ax b =无解,因此1λ=-.由()()r A r A =,得2a =-.( II ) 对增广矩阵做初等行变换31012111211121020102010102111100000000A ⎛⎫- ⎪----⎛⎫⎛⎫ ⎪⎪ ⎪⎪=-→-→- ⎪ ⎪ ⎪ ⎪ ⎪- ⎪⎝⎭⎝⎭ ⎪ ⎪⎝⎭可知原方程组等价为1323212x x x ⎧-=⎪⎪⎨⎪=-⎪⎩,写成向量的形式,即123332110210x x x x ⎛⎫⎪⎛⎫⎛⎫ ⎪ ⎪ ⎪⎪=+- ⎪ ⎪ ⎪⎪ ⎪ ⎪⎝⎭⎝⎭ ⎪ ⎪⎝⎭.因此Ax b =的通解为32110210x k ⎛⎫ ⎪⎛⎫ ⎪⎪⎪=+- ⎪ ⎪ ⎪ ⎪⎝⎭ ⎪ ⎪⎝⎭,其中k 为任意常数.(21)【解析】 ( I )由于二次型在正交变换x Qy =下的标准形为2212y y +,所以A 的特征值为1231,0λλλ===.由于Q 的第3列为,0,22T ⎛ ⎝⎭,所以A 对应于30λ=的特征向量为22T⎛ ⎝⎭,记为3α. 由于A 是实对称矩阵,所以对应于不同特征值的特征向量是相互正交的,设属于121λλ==的特征向量为()123,,Tx x x α=,则30T αα=,即13022x x +=. 求得该方程组的基础解系为()()120,1,0,1,0,1TTαα==-,因此12,αα为属于特征值1λ=的两个线性无关的特征向量.由于12,αα是相互正交的,所以只需单位化:())1212120,1,0,1,0,1T Tααββαα====-. 取()12302,,10002Q ββα⎛⎪⎪==⎝⎭,则110T Q AQ ⎛⎫ ⎪=Λ= ⎪ ⎪⎝⎭,且1TQ Q -=, 故 1102201011022TA Q Q ⎛⎫- ⎪ ⎪=Λ= ⎪ ⎪- ⎪⎝⎭. ( II )A E +也是实对称矩阵,A 的特征值为1,1,0,所以A E +的特征值为2,2,1,由于A E +的特征值全大于零,故A E +是正定矩阵.(22)【解析】当给出二维正态随机变量的的概率密度(),f x y 后,要求条件概率密度|(|)Y X f y x ,可以根据条件概率公式|(,)(|)()Y X X f x y f y x f x =来进行计算.本题中还有待定参数,A 要根据概率密度的性质求解,具体方法如下.()()22222222()(),xxy y y x x xy x X f x f x y dy A e dy A e dy Ae e dy +∞+∞+∞+∞-+--------∞-∞-∞-∞====⎰⎰⎰⎰2,x x -=-∞<<+∞.根据概率密度性质有()21x X f x dx edx A π+∞+∞--∞-∞===⎰,即1A π-=,故()2x X f x -=,x -∞<<+∞.当x -∞<<+∞时,有条件概率密度()()()22222222(),,,x xy y x xy y x y Y X X f x y f y x x y f x -+--+---==-∞<<+∞-∞<<+∞.(23)【解析】()()()22123~,1,~,,~,N B n N B n N B n θθθθ--()()()()31122331i i i E T E a N a E N a E N a E N =⎛⎫==++ ⎪⎝⎭∑()()221231a n a n a n θθθθ=-+-+()()212132na n a a n a a θθ=+-+-.因为T 是θ的无偏估计量,所以()E T θ=,即得()()12132010na n a a n a a =⎧⎪-=⎨⎪-=⎩,整理得到10a =,21,a n = 31a n=.所以统计量()()12323111110T N N N N N n N n n n n=⨯+⨯+⨯=⨯+=⨯-.注意到1(,1)N B n θ- ,故()()()11211D T D n N D N n n⎡⎤=⨯-=⨯⎢⎥⎣⎦()11n θθ=-.。
2010年考研数学三真题一.选择题1.若1])1(1[lim =--→xox e a xx 则a =A0 B1 C2 D32.设21,y y 是一阶线性非齐次微分方程)()(x q y x p y =+'的两个特解,若常数μλ,使21y y μλ+是该方程的解,21y y μλ-是该方程对应的齐次方程的解,则A 21,21==μλ B 21,21-=-=μλ C 31,32==μλ D 32,32==μλ3.设函数f(x),g(x)具有二阶导数,且.0)(<''x g 若a x g =)(0是g(x)的极值,则f(g(x))在0x 取极大值的一个充分条件是A 0)(<'a fB 0)(>'a fC 0)(<''a fD 0)(>''a f 4设1010)(,)(,ln )(xex h x x g x x f ===则当x 充分大时有Ag(x)<h(x)<f(x) Bh(x)<g(x)<f(x) Cf(x)<g(x)<h(x) Dg(x)<f(x)<h(x)5设向量组线性表示,,,:,可由向量组s I βββααα⋯⋯21r 21II ,,:,下列命题正确的是: A 若向量组I 线性无关,则s r ≤ B 若向量组I 线性相关,则r>sC 若向量组II 线性无关,则s r ≤D 若向量组II 线性相关,则r>s 6.设A 为4阶实对称矩阵,且02=+A A ,若A 的秩为3,则A 相似于A ⎪⎪⎪⎪⎪⎭⎫ ⎝⎛0111B ⎪⎪⎪⎪⎪⎭⎫ ⎝⎛-0111C ⎪⎪⎪⎪⎪⎭⎫ ⎝⎛--0111D ⎪⎪⎪⎪⎪⎭⎫ ⎝⎛---0111 7.设随机变量X 的分布函数⎪⎩⎪⎨⎧≥-<≤<=-1,110,21,0)(x e x x x F x,则P (X=1)=A0 B21 C 121--e D 11--e 8.设)(1x f 为标准正态分布概率密度,)(2x f 为[-1,3]上均匀分布的概率密度,若⎩⎨⎧<>≥≤=)0,0(0),(0),()(21b a x x bf x x af x f 为概率密度,则a,b 满足:A2a+3b=4 B3a+2b=4 Ca+b=1 Da+b=2二.填空题9.设可导函数y=y(x),由方程⎰⎰=+-xyx t dt t x dt e 020sin 2确定,则____________0==x dxdy10.设位于曲线)()ln 1(12+∞<≤+=x e x x y 下方,x 轴上方的无界区域为G ,则G 绕x轴旋转一周所得空间区域的体积为____________11.设某商品的收益函数R(p),收益弹性为31p +,其中p 为价格,且R(1)=1,则R(p)=________________12.若曲线123+++=bx ax x y 有拐点(-1,0),则b=_____________13.设A ,B 为3阶矩阵,且2,2,31=+==-B A B A ,则_________1=+-B A14.设___________ET ,1T )0)(,(N ,,122321==>⋯∑=则计量的简单随机样本。
2010考研数学(一)真题及参考答案一、选择题 (1)、极限2lim ()()xx xx a x b →∞⎛⎫=⎪-+⎝⎭( C ) A 、1 B 、e C 、a be - D 、b ae-【详解】()()2222ln 1()()()()()()()()lim lim lim ()()lim lim xx x xx x a x b x a x b x x x a b x ab a b x abxx x a x b x a x b x x a bxe ex a x b ee e ⎛⎫⎛⎫-⎪ ⎪ ⎪ ⎪-+-+⎝⎭⎝⎭→∞→∞→∞-+⎛⎫-+ ⎪ ⎪-+-+⎝⎭→∞→∞-⎛⎫== ⎪-+⎝⎭===(2)、设函数(,)z z x y =,由方程(,)0y z F x x =确定,其中F 为可微函数,且20F '≠,则z z xy u y∂∂+=∂∂( B )A 、xB 、zC 、x -D z -【详解】 等式两边求全微分得:121212()()()0x x y y z z Fu F v dx Fu F v dy Fu F v dz ''''''+++++=,所以有,1212xx z z Fu F v z x Fu F v ''+∂=-''∂+,1212y yz zFu F v z y Fu F v ''+∂=-''∂+, 其中,2x y u x =-,1y u x =,0z u =,2x z v x =-,0yv =,1z v x=,代入即可。
(3)、设,m n是正整数,则反常积分⎰的收敛性( D )(A)仅与m 的取值有关 (B)仅与n 有关(C)与,m n 都有关 (D)都无关 【详解】:显然0,1x x ==是两个瑕点,有=+⎰对于的瑕点0x =,当0x +→21ln (1)mn x x -=-等价于221(1)m m nx--,而21120m nxdx -⎰收敛(因,m n 是正整数211m n ⇒->-),故收敛;对于的瑕点1x =,当1(1,1)(0)2x δδ∈-<<12122ln (1)2(1)n m n m x x <-<-,而2112(1)m x -⎰显然收敛,故收敛。
2010年考研真题:数学二试题及参考答案2010年考研数学二试题及参考答案一、选择题(本大题共12小题,每小题5分,共60分)1.选出下列不等式的解集: (A) x^2 - 3x + 2 > 0 (B) x^2 - 3x + 2 ≥ 0(C) x^2 - 3x + 2 < 0 (D) x^2 - 3x + 2 ≤ 0 正确答案:(A)2.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 的单调增区间为: (A) (-∞, 1) (B) (1, +∞) (C) (-∞, 1]∪[2, +∞) (D) (1, 2) 正确答案:(C) 3.若 a, b, c 均为正整数,且 a + b + c = 11,则 a, b, c 的取值个数为: (A) 45 (B) 55 (C) 66 (D) 77 正确答案:(B)4.已知函数 f(x) = x^3 - 3x^2 + 2x - 1,则 f(x) 有重根的条件是: (A)f(1) = 0 (B) f'(1) = 0 (C) f''(1) = 0 (D) f'''(1) = 0 正确答案:(C) 5.设 a, b, c 均为正整数,且 a + b + c = 12,则 a, b, c 的不等式约束条件个数为: (A) 55 (B) 66 (C) 77 (D) 78 正确答案:(D)6.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 的极值点个数为: (A) 0(B) 1 (C) 2 (D) 3 正确答案:(A)7.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 在(0, +∞) 上的最大值为: (A) 2 (B) 3 (C) 4 (D) 5 正确答案:(D)8.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 在 (-∞, 0) 上的最小值为: (A) -2 (B) -3 (C) -4 (D) -5 正确答案:(A)9.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 的单调减区间为: (A) (0,1) (B) (1, +∞) (C) (-∞, 1]∪[2, +∞) (D) (1, 2) 正确答案:(B) 10.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 在(0, +∞) 上的最小值为: (A) -2 (B) -3 (C) -4 (D) -5 正确答案:(C)11.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 的零点个数为: (A) 0 (B)1 (C)2 (D)3 正确答案:(C)12.设函数 f(x) = x^3 - 3x^2 + 2x - 1, 则 f(x) 在 (-∞, 0) 上的最大值为: (A) 2 (B) 3 (C) 4 (D) 5 正确答案:(B)二、解答题(本大题共7小题,每小题10分,共70分)13.已知函数 f(x) = x^3 - 3x^2 + 2x - 1,求 f(x) 的极值点。
2010年考研数学一真题一、选择题(1~8小题,每小题4分,共32分。
下列每题给出的四个选项中,只有一个选项是符合题目要求的。
)(1)极限limx→∞[x2(x−a)(x+b)]x=(A)1 (B)e (C)e a−b(D)e b−a 【考点】C。
【解析】【方法一】这是一个“1∞”型极限lim x→∞[x2(x−a)(x+b)]x=limx→∞{[1+(a−b)x+ab(x−a)(x+b)](x−a)(x+b)(a−b)x+ab}(a−b)x+ab(x−a)(x+b)x=e a−b【方法二】原式=limx→∞e xlnx2(x−a)(x+b)而limx→∞ xln x2(x−a)(x+b)=limx→∞xln(1+(a−b)x+ab(x−a)(x+b))=limx→∞x∙(a−b)x+ab(x−a)(x+b)(等价无穷小代换) =a−b则limx→∞[x2(x−a)(x+b)]x=e a−b【方法三】对于“1∞”型极限可利用基本结论:若limα(x)=0, limβ(x)=0,且limα(x)β(x)=A 则li m(1+α(x))β(x)=e A,求极限由于limx→∞α(x)β(x)=limx→∞x2−(x−a)(x+b)(x−a)(x+b)∙x=limx→∞(a−b)x2+abx(x−a)(x+b)=a−b则limx→∞[x2(x−a)(x+b)]x=e a−b【方法四】lim x→∞[x2(x−a)(x+b)]x=limx→∞[(x−a)(x+b)x2]−x=limx→∞(1−ax)−x∙limx→∞(1+bx)−x=e a∙e−b=e a−b综上所述,本题正确答案是C。
【考点】高等数学—函数、极限、连续—无穷小量的性质及无穷小量的比较,极限的四则运算,两个重要极限(2)设函数z=z(x,y)由方程F(yx ,zx)=0确定,其中F为可微函数,且f′′2≠0,则xðzðx +yðzðy=。
2010年国考真题与解析第三部分:判断推理(共35题,参考时限35分钟)、图形推理请按每道题的答题要求作答。
请开始答题:56. 从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性:【QZZN答案选A】【田老鼠解析】给定项分别对应3、4、5、6、7的三角形,所以未知项应该是8个三角形,即A 选项。
57. 从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性:【QZZN答案选D】【田老鼠解析】所给项都是轴对称图形。
第一张图有一条水平的对称轴,第二张图有一条竖直的对称轴,第三张和第四张图都有水平和竖直的对称轴各一条,第五幅图有一条竖直的对称轴,所以下幅图应有一条水平的对称轴,符合条件的只有D项【2010国考行测真题讨论】第57题图形推理/read-htm-tid-11283500.html 58. 从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性:【QZZN答案选D】【田老鼠解析】题干中所给黑色小图形与外面的大图形是相同的,只有D选项符合这一特征。
59. 从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性:【QZZN答案选B】【田老鼠解析】题干中,小图形都以90度的顺时针方向在大图形的内部或是外部做旋转。
60. 从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性:【QZZN答案选C】【田老鼠解析】每行的白圈个数分别为9、8、7,排除掉B项、D项。
小黑圆圈每次依着向右,右边无圆圈则向下的顺序每次移动两格(下幅图中被消去的小白圆圈不计算在移动格子内),所以符合条件的只有C项【PUKI解析】黑点每次从左到右移动2个位置,每行白点的布局均有所不同(但是每行都是9,8,7个白点),考虑白点变化将相当复杂,因此我们就盯上黑点的移动,就可以解题了。
黑点每次在上一图位置出发在下一图的布局中从左到右移动2个位置,故选C。
在这里白点的设置我觉得是陷阱,让人迷乱的陷阱。
Section I Use of EnglishDirections:Read the following text. Choose the best word(s) for each numbered blank and mark [A], [B], [C] or [D] on ANSWER SHEET 1. (10 points)In 1924 American’ National Research Council sent to engineers to supervise a series o f industrial experiments at a large telephone-parts factory called the Hawthorne Plant near Chicago. It hoped they would learn how stop-floor lignting__1__workers productivity. Instead, the studies ended __2___giving their name to the “Hawthorne effect”, t he extremely influential idea that the very___3____to being experimented upon changed subjects’ behavior.The idea arose because of the __4____behavior of the women in the Hawthorne plant. According to __5____of the experiments, their hourly output rose when lighting was increased, but also when it was dimmed. It did not __6____what was done in the experiment; ___7_someting was changed ,productivity rose. A(n)___8___that they were being experimented upon seemed to be ____9___to alter workers’ behavior ____10____itself.After several decades, the same data were _11__ to econometric the analysis. Hawthorne experiments has another surprise store _12 __the descriptions on record, no systematic _13__ was found that levels of productivity were related to changes in lighting.It turns out that peculiar way of conducting the experiments may be have let to__ 14__ interpretation of what happed.__ 15___ , lighting was always changed on a Sunday .When work started again on Monday, output __16___ rose compared with the previous Saturday and__ 17 __to rise for the next couple of days.__ 18__ , a comparison with data for weeks when there was no experimentation showed that output always went up on Monday, workers__ 19__ to be diligent for the first few days of the week in any case , before __20 __a plateau and then slackening off. This suggests that the alleged” Hawthorne effect “ is hard to pin down.1. [A] affected [B] achieved [C] extracted [D] restored2. [A] at [B]up [C] with [D] off3. [A]truth [B]sight [C] act [D] proof4. [A] controversial [B] perplexing [C]mischievous [D] ambiguous5. [A]requirements [B]explanations [C] accounts [D] assessments6. [A] conclude [B] matter [C] indicate [D] work7. [A] as far as [B] for fear that [C] in case that [D] so long as8. [A] awareness [B] expectation [C] sentiment [D] illusion9. [A] suitable [B] excessive [C] enough [D] abundant10. [A] about [B] for [C] on [D] by11. [A] compared [B]shown [C] subjected [D] conveyed12. [A] contrary to [B] consistent with [C] parallel with [D] pealliar to13. [A] evidence [B]guidance [C]implication [D]source14. [A] disputable [B]enlightening [C]reliable [D]misleading15. [A] In contrast [B] For example [C] In consequence [D] As usual16. [A] duly [B]accidentally [C] unpredictably [D] suddenly17. [A]failed [B]ceased [C]started [D]continued20. [A]breaking [B]climbing [C]surpassing [D]hitingSection II Reading ComprehensionPart ADirections:Read the following four texts. Answer the questions below each text by choosing [A], [B], [C] or [D]. Mark your answers on ANSWER SHEET 1. (40 points)Text 1Of all the changes that have taken place in English-language newspapers during the past quarter-century, perhaps the m ost far-reaching has been the inexorable decline in the scope and seriousness of their arts coverage.It is difficult to the point of impossibility for the average reader under the age of forty to imagine a time when high-quality arts criticism could be found in most big-city newspapers. Yet a considerable number of the most significant c ollections of criticism published in the 20th century consisted in large part of new spaper reviews. To read such books today is to marvel at the fact that their learned contents were once deemed suitable for publication in general-circulation dailies.We are even farther rem oved from the unfocused newspaper review spublished in England between the turn of t he 2 0th century and the eve of World War Ⅱ, at a time when newsprint was dirt-cheap and stylish arts crit icism was consi dered an ornament to the publications in which it appe ared. In those far-off days, it was taken for granted tha t the cri tics of major papers woul dwri te in detail and at length about the events they covered. Theirs was a serious business, and even those reviewers who wore their learning lightly, like George Bern ard Shaw and Ernest Newman, could be trus ted to know what they were a bout. These men believed in journalism as a calling, and were proud to be published in the daily press. “So few authors have brains enough or literary gift enough to keep their own end upin journalism, ”Newman wrote, “ that I am tempted to define‘journalism’ as ‘a term of cont empt appl ied by writers who are not read to writers who are’. ”Unfortunately, these critics are virtually forgotten. Neville Cardus, who wrote for the Manchester Guardian from 1917 until shortly before his death in 1975, is now known solely as a writer of essays ont he game of cricket. During his l ifetime, though, he was also one of England's foremost classical-music critics, and a stylist so widely admired that his Autobiography(1947)became a best-seller. He was knighted in 1967, the first music critic to be so ho nored. Yet on ly one of his books is now in print, and his vast body of writings on music is unknown save to specialists.Is there any chance that Cardus’s criticism will enjoy a revi val? The prospect seems remote. Jour nalistic tastes had changed long before his death, and postmodern reader shave little use for the ric hly upholstered Vicwardian prose in which he specialized. Moreover, the amateur tradition in music criticism has been in headlong retreat.21. It is indicated in Paragraphs 1 and 2 that[A] arts criticism has disappeared from big-city newspapers.[B] English-language newspapers used to carry more arts reviews.[C] high-quality newspapers retain a large body of readers.[D] young readers doubt the suitability of criticism on dailies.22. Newspaper reviews in England before world warⅡwere characterized by[A] free themes.[B] casual style.[C] elaborate layout.[D] radical viewpoints.23. which of the following would Shaw and Newman most probably agree on?[A] It is writers’ duty to fulfill journalistic goals.[B] It is contemptible for writers to be journalists.[C] Writers are likely to be tempted into journalism.[D] Not all writers are capable of journalistic writing.24. What can be learned about Cardus according to the last two paragraphs?[A] His music criticism may not appeal to readers today.[B] His reputation as a music critic has long been in dispute.[C]His style caters largely to modern specialists.[D]His writings fail to follow the amateur tradition.25. What would be the best title for the text?[A] Newspapers of the Good Old Days.[B] The lost Horizon in Newspapers.[C] Mournful Decline of Journalism.[D] Prominent Critics in Memory.Text 2Over the past decade, thousands of patents have been granted for what are called business methods. received one for its “one-click” online payment system. Merrill Lynch got legal protection for an asset allocation strategy. One inventor patented a technique for lifting a box.Now the nation’s top patent court appears completely ready to scale back on business-method patents, which have been controversial ever since they were first authorized 10 years ago. In a move that has intellectual-property lawyers abuzz the U.S. court of Appeals for the federal circuit said it would use a particular case to conduct a broad review of business-method patents. In re Bilski , as the case is known , is “a very big deal”, says Dennis’D. Crouch of the University of Missouri School of law. It “has the potential to eliminate an entire class of patents.”Curbs on business-method claims would be a dramatic about-face, because it was the federal circuit itself that introduced such patents with is 1998 decision in the so-called state Street Bank case, approving a patent on a way of pooling mutual-fund assets. That ruling produced an explosion in business-method patent filings, initially by emerging internet companies trying to stake out exclusive pinhts to specific types of online transactions. Later, move established companies raced to add such patents to their files, if only as a defensive move against rivals that might beat them to the punch. In 2005, IBM noted in a court filing that it had been issued more than 300 business-method patents despite the fact that it questioned the legal basis for granting them. Similarly, some Wall Street investment films armed themselves with patents for financial products, even as they took positions in court cases opposing the practice.The Bilski case involves a claimed patent on a method for hedging risk in the energy market. The Federal circuit issued an unusual order stating that the case would be heard by all 12 of the court’s judge s, rather than a typical panel of three, and that one issue it wants to evaluate is whether it should” reconsider” its state street Bank ruling.The Federal Circuit’s action comes in the wake of a series of recent decisions by the supreme Count that has narrowed the scope of protections for patent holders. Last April, for example the justices signaled that too many patents were being upheld for “inventions” that are obvious. The judges on the Federal circuit are “reacting to the anti_ patent trend at the supreme court” ,says Harole C.wegner, a partend attorney and professor at aeorge Washington University Law School.26. Business-method patents have recently aroused concern because of[A] their limited value to business[B] their connection with asset allocation[C] the possible restriction on their granting[D] the controversy over authorization27. Which of the following is true of the Bilski case?[A] Its ruling complies with the court decisions[B] It involves a very big business transaction[C] It has been dismissed by the Federal Circuit[D] It may change the legal practices in the U.S.28. The word “about-face” (Line 1, Paro 3) most probably means[A] loss of good will[B] increase of hostility[C] change of attitude[D] enhancement of dignity29. We learn from the last two paragraphs that business-method patents[A] are immune to legal challenges[B] are often unnecessarily issued[C] lower the esteem for patent holders[D] increase the incidence of risks30. Which of the following would be the subject of the text?[A] A looming threat to business-method patents[B] Protection for business-method patent holders[C] A legal case regarding business-method patents[D] A prevailing trend against business-method patentsText 3In his book The Tipping Point, Malcolm Aladuell argues that social epidemics are driven in large part by the acting of a tiny minority of special individuals, often called influentials, who are unusually informed, persuasive, or well-connected. The idea is intuitively compelling, but it doesn’t explain how ideas actually spread.The supposed importance of influentials derives from a plausible sounding but largely untested theory called the “two step flow of communication”: Information flows from the media to the influentials and from them to everyone else. Marketers have embraced the two-step flow because it suggests that if they can just find and influence the influentials, those selected people will do most of the work for them. The theory also seems to explain the sudden and unexpected popularity of certain looks, brands, or neighborhoods. In many such cases, a cursory search for causes finds that some small group of people was wearing, promoting, or developing whatever it is before anyone else paid attention. Anecdotal evidence of this kind fits nicely with the idea that only certain special people can drive trendsIn their recent work, however, some researchers have come up with the finding that influentials have far less impact on social epidemics than is generally supposed. In fact, they don’t seem to be required of all.The researchers’ argument stems from a simple observing about social influence, with the exception of a few celebrities like Oprah Winfrey-whose outsize presence is primarily a function of media, not interpersonal, influence-even the most influential members of a population simply don’t interact with that many others. Yet it is precisely these non-celebrity influentials who, according to the two-step-flow theory, are supposed to drive social epidemics by influencing their friends and colleagues directly. For a social epidemic to occur, however, each person so affected, must then influence his or her own acquaintances, who must in turn influence theirs, and so on; and just how many others pay attention to each of these people has little to do with the initial influential. If people in the network just two degrees removed from the initial influential prove resistant, for example from the initial influential prove resistant, for example the cascade of change won’t propagate very far or affect many people.Building on the basic truth about interpersonal influence, the researchers studied the dynamics of populations manipulating a number of variables relating of populations, manipulating a number of variables relating to peopl e’s ability to influence others and their tendency to be influenced. Our work shows that the principal requirement for what we call “global cascades”- the widespread propagation of influence through networks - is the presence not of a few influentials but, rather, of a critical mass of easily influenced people, each of whom adopts, say, a look or a brand after being exposed to a single adoptingneighbor. Regardless of how influential an individual is locally, he or she can exert global influence only if this critical mass is available to propagate a chain reaction.31.By citing the book The Tipping Point, the author intends to[A]analyze the consequences of social epidemics[B]discuss influentials’ function in spreading ideas[C]exemplify people’s intuitive response to social epidemics[D]describe the essential characteristics of influentials.32.The author suggests that the “two-step-flow theory”[A]serves as a solution to marketing problems[B]has helped explain certain prevalent trends[C]has won support from influentials[D]requires solid evidence for its validity33.what the researchers have observed recently shows that[A] the power of influence goes with social interactions[B] interpersonal links can be enhanced through the media[C] influentials have more channels to reach the public[D] most celebrities enjoy wide media attention34.The underlined phrase “these people” in paragraph 4 refers to the ones who[A] stay outside the network of social influence[B] have little contact with the source of influence[C] are influenced and then influence others[D] are influenced by the initial influential35.what is the essential element in the dynamics of social influence?[A]The eagerness to be accepted[B]The impulse to influence others[C]The readiness to be influenced[D]The inclination to rely on othersText 4Bankers have been blaming themselves for their troubles in public. Behind the scenes, they have been taking aim at someone else: the accounting standard-setters. Their rules, moan the banks, have forced them to report enormous losses, and it’s just not fair. These rules say they must value some assets at the price a third party would pay, not the price managers and regulators would like them to fetch.Unfortunately, banks’ lobbying now seems to be work ing. The details may be unknowable, but the independence of standard-setters, essential to the proper functioning of capital markets, is being compromised. And, unless banks carry toxic assets at prices that attract buyers, reviving the banking system will be difficult.After a bruising encounter with Congress, America’s Financial Accounting Standards Board (FASB) rushed through rule changes. These gave banks more freedom to use models to value illiquid assets and more flexibility in recognizing losses on long-term assets in their income statement. Bob Herz, the FASB’s chairman, cried out against those who “question our motives.” Yet bank shares rose and the changes enhance what one lobby group politely calls “the use of judgment by management.”European ministers instantly demanded that the International Accounting Standards Board (IASB) do likewise. The IASB says it does not want to act without overall planning, but the pressure to fold when it completes it reconstruction of rules later this year is strong. Charlie McCreevy, a European commissioner, warned the IASB that it did “not live in a political vacuum” but “in the real word” and that Europe could yet develop different rules.It was banks that were on the wrong planet, with accounts that vastly overvalued assets. Today they argue that market prices overstate losses, because they largely reflect the temporary illiquidity of markets, not the likely extent of bad debts. The truth will not be known for years. But bank’s shares trade below their book value, suggesting that investors are skeptical. And dead markets partly reflect the paralysis of banks which will not sell assets for fear of booking losses, yet are reluctant to buy all those supposed bargains.To get the system working again, losses must be rec ognized and dealt with. America’s new plan to buy up toxic assets will not work unless banks mark assets to levels which buyers find attractive. Successful markets require independent and even combative standard-setters. The FASB and IASB have been exactly that, cleaning up rules on stock options and pensions, for example, against hostility form special interests. But by giving in to critics now they are inviting pressure to make more concessions.36. Bankers complained that they were forced to[A] follow unfavorable asset evaluation rules[B]collect payments from third parties[C]cooperate with the price managers[D]reevaluate some of their assets.37.According to the author , the rule changes of the FASB may result in[A]the diminishing role of management[B]the revival of the banking system[C]the banks’ long-term asset losses[D]the weakening of its independence38.According to Paragraph 4, McCreevy objects to the IASB’s attempt to[A]keep away from political influences.[B]evade the pressure from their peers.[C]act on their own in rule-setting.[D]take gradual measures in reform.39.The author thinks the banks were “on the wrong planet ”in that they[A]misinterpreted market price indicators[B]exaggerated the real value of their assets[C]neglected the likely existence of bad debts.[D]denied booking losses in their sale of assets.40.The author’s attitude towards standard-setters is one of[A]satisfaction.[B]skepticism.[C]objectiveness[D]sympathyPart BDirections:For Questions 41-45, choose the most suitable paragraphs from the list A-G and fill them into the numbered boxes to form a coherent text. Paragraph E has been correctly placed. There is one paragraph which dose not fit in with the text. Mark your answers on ANSWER SHEET1. (10 points)[A] Th e first and more important is the consumer’s growing preference for eating out; the consumption of food and drink in places other than homes has risen from about 32 percent of total consumption in 1995 to 35 percent in 2000 and is expected to approach 38 percent by 2005. This development is boosting wholesale demand from the food service segment by 4 to 5 percent a year across Europe, compared with growth in retail demand of 1 to 2 percent. Meanwhile, as the recession is looming large, people are getting anxious. They tend to keep a tighter hold on their purse and consider eating at home a realistic alternative.[B] Retail sales of food and drink in Europe’s largest markets are at a standstill, leaving European grocery retailers hungry for opportunities to grow. Most leading retailers have already tried e-commerce, with limited success, and expansion abroad. But almost all have ignored the big, profitable opportunity in their own backyard: the wholesale food and drink trade, which appears to be just the kind of market retailers need.[C] Will such variations bring about a change in the overall structure of the food and drink market? Definitely not. The functioning of the market is based on flexible trends dominated by potential buyers. In other words, it is up to the buyer, rather than the seller, to decide what to buy .At any rate, this change will ultimately be acclaimed by an ever-growing number of both domestic and international consumers, regardless of how long the current consumer pattern will take hold.[D] All in all, this clearly seems to be a market in which big retailers could profitably apply their scale, existing infrastructure and proven skills in the management of product ranges, logistics, and marketing intelligence. Retailers that master the intricacies of wholesaling in Europe may well expect to rake in substantial profits thereby. At least, that is how it looks as a whole. Closer inspection reveals important differences among the biggest national markets, especially in their customer segments and wholesale structures, as well as the competitive dynamics of individual food and drink categories. Big retailers must understand these differences before they can identify the segments of European wholesaling in which their particular abilities might unseat smaller but entrenched competitors. New skills and unfamiliar business models are needed too.[E] Despite variations in detail, wholesale markets in the countries that have been closely examined-France, Germany, Italy, and Spain-are made out of the same building blocks. Demand comes mainly from two sources: independent mom-and-pop grocery stores which, unlike large retail chains, are two small to buy straight from producers, and food service operators that cater to consumers when they don’t eat at home. Such food service operators range from snack machines to large institutional catering ventures, but most of these businesses are known in the trade as “horeca”: hotels, restaurants, and cafes. Overall, Europe’s wholesale market for food and drink is grow ing at the same sluggish pace as the retail market, but the figures, when added together, mask two opposing trends.[F] For example, wholesale food and drink sales come to $268 billion in France, Germany, Italy, Spain, and the United Kingdom in 2000-more than 40 percent of retail sales. Moreover, average overall margins arehigher in wholesale than in retail; wholesale demand from the food service sector is growing quickly as more Europeans eat out more often; and changes in the competitive dynamics of this fragmented industry are at last making it feasible for wholesalers to consolidate.[G] However, none of these requirements should deter large retailers (and even some large good producers and existing wholesalers) from trying their hand, for those that master the intricacies of wholesaling in Europe stand to reap considerable gains.Part CDirections:Read the following text carefullyand then translate the underlined segments into Chinese. Your translation should bewritten clearly on ANSWER SHEET 2. (10 points)One basic weakness in a conservation system based wholly on econom ic motives is that most members of the land community have no economic value. Yet these creatures are members of the biotic community and, if its stability depends on its integrity, they are entitled to continuance.When one of these noneconomic categories is threatened and, if we happen to love it, we invent excuses to give it economic importance. At the beginning of the century songbirds were supposed to be disappearing.(46)Scientists ju mped to the rescue with some distinctly shaky evidence to the effect that insects would eat us up if birds failed to control them. The evidence had to be economic in order to be valid.It is painful to read these roundabout accounts today. We have no land ethic yet, (47) but we have at least drawn nearer the point of adm itting that birds should continue as a matter of intrinsic right, regardless of the presence or absence of economic advantage to us.A parallel situation exists in respect of predatory mammals and fish-eating birds. (48) Time was when biologists som ewhat overworked the evidence that these creatures preserve the health of game by killing the physically weak, or that they prey only on “worthless” species. Here again, the evidence had to be economic in order to be valid. It is only in recent years that we hear the more honest argumentthat predators are members of the community, and that no special interest has the right to exte rminate the m f or the sake of a benefit, real or fancied, to itself.Some species of tree have been“read out of the party” by economics-minded foresters because they grow too slowly, or have too low a sale value to pay as timber crops.(49) In Europe, where forestry is ecologically more advanced, the noncommercial tree species are recognized as members of native forest community, to be preserved as such, within reason. Moreover, some have been found to have a valuable function in building up soil fertility. The interdependence of the forest and its constit uent tree species, ground flora, and fauna is taken for granted.To sum up: a systemof conservation based solely on economic self-interest is hopelessly lopsided. (50) It tends to ignore , and thus eventually to eliminate, many elements in the land community that lack commercial value,but that are essential to its healthy functioning. It assumes, falsely, that the economic parts of the biotic clock will function without the uneconomic parts.Section III WritingPart A51. Directions:You are supposed to write for the Postgraduates’ Associ ation a notice to recruit volunteers for an international c onference on globalization. The notice should include the basic qualificationsof applicants and other information which you think is relevant.You should write about 100 words on ANSWER SHEET 2.Do not sign your own nam e at the end of the notice. Use "postgraduates’ Association" instead.(10 points)Part B52. Directions:Write an essay of 160-200 words based on the following drawing. In your essay, you should1) describe the drawing briefly,2) explain its intended meaning, and3) give your comments.You should write neatly on ANSWER SHEET 2. (20 points)2010年答案:Section I: Use of English (10 points)Section II: Reading Comprehension (60 points)Part A (40 points)Part B (10 points)Part C (10 points)46 . 科学家们赶紧拿出某些明显站不住脚的证据来补救,大致说的是如果鸟儿不能控制昆虫数量的话,昆虫就会把我们吃光。