2015年武汉科技大学820 工业工程基础-2015(A卷答案)年考研真题／研究生入学考试试题
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年攻读硕士学位研究生入学考试试题参考答案科目名称：工业工程基础（□√A 卷□B 卷）科目代码：考试时间：3小时 满分 150 √□计算器 □直尺 □圆规（请在使用工具前打√）小题，每小题 2分，共30分) 分）工业工程的职能分为规划、设计、评价、创新等四个方面。分）工作抽样中获得记录结果的概率分布为正态分布。分）标准时间由作业时间和宽放时间组成。 分）工作研究中观察和记录现行方法，以及对现行方法分析改进，需要运用的提问技
2015年考研英语二真题答案(完整版)
2015年考研英语二真题答案（完整版） 2015考研英语二答案 完型填空题 1 .C signal 2 .D much 3. C plugged 4. A message 5. C behind 6. A misinterpreted 7. B judged 8. D unfamiliar 9. B anxious 10. D turn 11.A dangerous 12. A hurt 13.B conversation 14. D passengers 15.C predict 16. D ride 17.A went through 18.C in fact 19.B since 20 B simple 阅读题答案 Text 1 答案 21. D offered greater relaxation than the workplace 22. B childless husbands 23. A they are both bread winners and housewives 24. C earnings 25. B division of labor at home is seldom clear-cut Text2 答案 26. C miss its original purpose 27. A the problem is solvable 28. C are in need offinancial support 29. D are inexperienced in handling issues at college
30. D colleges are partly responsible for the problem in question Text3 答案 31. A more emotional 32. C sports culture 33.D strengthen employee loyalty 34.A voices for working women 35. C companies find it to be fundamental Text4 36. B the increase of voluntary part-time jobs 37. C cannot get their hands on full-time jobs 38. B shows a general tendency of decline 39. B empolyment is no longer a precondition to get insureance 40.A 阅读新题型 41 .D Most of your fearsare unreal 42. E Think about the [resent moment 43.G There are many things to be grateful for 44.A You are not alone 45. C Pave your own unique path 翻译题 回想一下这样的经历：开车行驶在一条非常熟悉的道路上。这可能是你每天上下班的必经之路，可能是进城的旅行，亦或是回家的道路。不管是哪一种，你都了解每一个屈折拐弯之处，就像熟悉自己手背上的纹路一样。在这些所有类型的旅途中，很容易失去驾车的注意力，并且几乎不注意沿途的风景。结果，比起这段路途实际需要的时间，你的感觉是花费的时间更少。 这就是经常旅行线路效应：人们往往低估了花费在一条熟悉的路线上的时间。 这种效应是由于我们分配注意力的方式引起的。当我们旅行一条非常著名的路线时，因为我们不是非得注意太多，时间似乎流逝得更快。然后，当我们回忆起这段旅程时，因为我们没有花费太多的注意力，因此我们对之记忆地不太清楚，所以我们认为这段旅行更为短途作文 PART A 【参考范文1】 Notice In order to enrich high school students’ life in summer holiday and expand the reputation of our university, the Students Union are going to host a summer camp in our school campus and volunteers are needed. The details about this summer camp and volunteer recruitment are listed as follows. Firstly, the summer camp will begin on September 1st and it will last for ten days. Secondly, the main theme of this summer camp is “Better English, Better life” and there are various activities in this summer camp, including English-speaking contest, drama contest, sports meeting and
2015年考研数学一真题与解析
2015年考研数学一真题 一、选择题 1—8小题．每小题4分，共32分． １．设函数()f x 在(,)-∞+∞上连续，其二阶导数()f x ''的图形如右图所示，则曲线()y f x =在(,)-∞+∞的拐点个数为 （A ）0 （B ）1 （C ）2 （D ）3 【详解】对于连续函数的曲线而言，拐点处的二阶导数等于零或者不存在．从图上可以看出有两个二阶导数等于零的点，以及一个二阶导数不存在的点0x =．但对于这三个点，左边的二阶导数等于零的点的两侧二阶导数都是正的，所以对应的点不是拐点．而另外两个点的两侧二阶导数是异号的，对应的点才是拐点，所以应该选（C ） 2．设211 23 ()x x y e x e = +-是二阶常系数非齐次线性微分方程x y ay by ce '''++=的一个特解，则 （A ）321,,a b c =-==- （B ）321,,a b c ===- （C ）321,,a b c =-== （D ）321,,a b c === 【详解】线性微分方程的特征方程为2 0r ar b ++=，由特解可知12r =一定是特征方程的一个实根．如果21r =不是特征方程的实根，则对应于()x f x ce =的特解的形式应该为()x Q x e ，其中()Q x 应该是一个零次多项式，即常数，与条件不符，所以21r =也是特征方程的另外一个实根，这样由韦达定理可得 213212(),a b =-+=-=?=，同时*x y xe =是原来方程的一个解，代入可得1c =-应该选（A ） ３．若级数 1 n n a ∞ =∑ 条件收敛，则3x x ==依次为级数 1 1() n n n na x ∞ =-∑的 （Ａ）收敛点，收敛点 （Ｂ）收敛点，发散点 (Ｃ）发散点，收敛点 （Ｄ）发散点，发散点 【详解】注意条件级数 1 n n a ∞ =∑条件收敛等价于幂级数 1 n n n a x ∞ =∑在1x =处条件收敛，也就是这个幂级数的 收敛为1，即11lim n n n a a +→∞=，所以11()n n n na x ∞ =-∑的收敛半径1 11lim ()n n n na R n a →∞+==+，绝对收敛域为02(,) ，显然3x x ==依次为收敛点、发散点，应该选（B ） ４．设D 是第一象限中由曲线2141,xy xy == 与直线,y x y ==所围成的平面区域，函数(,)f x y 在
2015年考研英语二阅读Text1真题详解
2015年考研英语二阅读Text1真题详解 整篇文章的主题是与我们生活息息相关的内容，文章的难度不大，相比2014年英语二的阅读来说，难度稳定，这是在我们预料之中的。 第21题According to Paragraph 1,most previous surveys found that home＿＿＿(根据第一段可知，之前的调查中认为家是一个____地方)。[A] offered greater relaxation than the workplace [B] was an ideal place for stress measurement [C] generated more stress than the workplace [D] was an unrealistic place for relaxation题目中明确给出范围，所以我们只要在第一段中找答案，且要注意题目中的关键词是previous。回归第一段，不难发现文章的首句便是答案出处：A new study suggests that contrary to most surveys, people are actually more stressed at home than at work.（新的研究显示不同于以往的绝大多数调查，人们在家比工作时的压力更大）。这句话中new、contrary to most surveys是提示词，与题目中的previous study相对应的，不难做出正确答案是[A] 第22题According to Damaske, who are likely to be the happiest at home?（Damaske 认为，谁可能是最家里最快乐的？）读完题目，回到文章第二段找Damaske的观点：It is men, not women, who report being happier at home than at work.在家男性比女性更快乐，Another surprise is that findings hold true for both those with children and without, but more so for nonparents.这句话的关键词是more,它与题目中的happiest最高级是相对应的，所以解这道题的关键便是nonparents.但是对于很多同学来说，nonparents是个生词，不认识。其实大家只要上过中公考研的英语词汇课，学习过词根词缀法，这个单词就变的很简单。nonparents是由否定前缀non-+parents构成的，non-这个否定前缀表示“不无非”，所以整个单词可以译为不是父母。四个选项[A] Childless wives [B] Working mothers [C] Childless husbands [D] Working fathers，我们可以轻易选出答案C，没有孩子且是丈夫。 第23题，The blurring of working women's roles refers to the fact that＿＿。回归第三段中，找到With the blurring of roles，发现前面的句子正是对这种现象的解释：for women who work outside the home, they often are playing catch-up-with-household tasks.以及后面的the home front lags well behind the workplace a making adjustments for working women，指的便是女性不仅得工作赚钱，而且还得在家得忙家务，所以她们的身份是双重的。所以选[D] they are both bread winners and housewives. 第24题，The word“ moola”(Line4,Para4)most probably means＿＿这是一道词义推测题，它与前文中的marking money是近义词，答案选[C] earnings收入。 第25题The home front differs from the workplace in that＿＿。文章第5段there are inadequate rewards for most of them. Your home colleagues-your family-have no clear rewards for their labor;家务劳动不会像工作一样得到足够的奖励，而且分工也是不明确的。答案对应选项[A] division of labor at home is seldom clear-cut. 虽然有突破口、也有规律可循，但这并不意味着我们可以一劳永逸、高枕无忧，要知道，
2015年考研数学真题答案(数一-)
2015年全国硕士研究生入学统一考试数学一试题答案 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、设函数()f x 在∞∞（-,+）连续，其2阶导函数()f x ''的图形如下图所示，则曲线()y f x =的拐点个数为（） （A ）0 （B ）1 （C ）2 （D ）3 【答案】(C) 【考点】拐点的定义 【难易度】★★ 【详解】拐点出现在二阶导数等于0，或二阶导数不存在的点上，并且在这点的左右两侧二阶导数异号，因此，由()f x ''的图形可知，曲线()y f x =存在两个拐点，故选(C). 2、设21123x x y e x e ?? =+- ?? ?是二阶常系数非齐次线性微分方程x y ay by ce "+'+=的一个特解，则（） （A ）3,1, 1.a b c =-=-=- （B ）3,2, 1.a b c ===- （C ）3,2, 1.a b c =-== （D ）3,2, 1.a b c === 【答案】(A) 【考点】常系数非齐次线性微分方程的解法 【难易度】★★ 【详解】 211,23 x x e e -为齐次方程的解，所以2、1为特征方程2+0a b λλ+=的根，从而()123,122,a b =-+=-=?=再将特解x y xe =代入方程32x y y y ce "-'+=得： 1.c =-
3、若级数 1 n n a ∞ =∑条件收敛，则x = 3x =依次为幂级数()1 1n n n na x ∞ =-∑的： （A ）收敛点，收敛点 （B ）收敛点，发散点 （C ）发散点，收敛点 （D ）发散点，发散点 【答案】(B) 【考点】级数的敛散性 【难易度】★★★ 【详解】因为 1 n n a ∞=∑条件收敛，故2x =为幂级数()1 1n n n a x ∞ =-∑的条件收敛点，进而得 ()11n n n a x ∞ =-∑的收敛半径为1，收敛区间为()0,2，又由于幂级数逐项求导不改变收敛区间，故 () 1 1n n n na x ∞ =-∑的收敛区间仍为()0,2，因而x = 3x =依次为幂级数()1 1n n n na x ∞ =-∑的收敛 点、发散点. 4、设D 是第一象限中曲线21,41xy xy ==与直线,y x y ==围成的平面区域，函数(,)f x y 在D 上连续，则 (,)D f x y dxdy =?? （A ） 12sin 21 4 2sin 2(cos ,sin )d f r r rdr π θπθθθθ?? （B ）24 (cos ,sin )d f r r rdr π πθθθ? （C ） 13sin 21 4 2sin 2(cos ,sin )d f r r dr πθπθ θθθ?? （D ）34 (cos ,sin )d f r r dr π πθθθ? 【答案】(D) 【考点】二重积分的极坐标变换 【难易度】★★★ 【详解】由y x =得，4 π θ= ；由y =得，3 π θ= 由21xy =得，2 2cos sin 1, r r θθ== 由41xy =得，2 4cos sin 1, r r θθ==
2015年全国硕士研究生招生考试英语(一)试题(完整版)及参考答案
2015 年全国硕士研究生入学统一考试英语一试题Section 1 Use of English Directions: 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) Though not biologically related, friends are as related as fourth cousins, sharing about 1% of genes. That is 1 a study published from the University of California and Yale University in the Proceedings of the National Academy of Sciences, has 2 . The study is a genome-wide analysis conducted 3 1932 unique subjects which 4 pairs of unrelated friends and unrelated strangers. The same people were used in both 5 .While 1% may seem 6 , it is not so to a geneticist. As James Fowler, professor of medical genetics at UC San Diego, says, Most people do not even 7 their fourth cousins but somehow manage to select as friends the people who 8 our kin. The study 9 found that the genes for smell were something shared in friends but not genes for immunity. Why this similarity in olfactory genes is difficult to explain, for now. 10 Perhaps, as the team suggests, it draws us to similar environments but there is more 11 it. There could be many mechanisms working in tandem that 12 us in choosing genetically similar friends 13 than nal kinship of being friends with 14 !One of the remarkable
2015年考研英语一真题及答案
Section I Use of English Directions: Read the following text.Choose the best word(s)for each numbered blank and mark A,B,C or D on ANSWER SHEET.(10points) Though not biologically related,friends are as“related”as fourth cousins, sharing about1%of genes.That is_(1)_a study,published from the University of California and Yale University in the Proceedings of the National Academy of Sciences, has__(2)_. The study is a genome-wide analysis conducted_(3)__1,932unique subjects which __(4)__pairs of unrelated friends and unrelated strangers.The same people were used in both_(5)_. While1%may seem_(6)_,it is not so to a geneticist.As James Fowler,professor of medical genetics at UC San Diego,says,“Most people do not even_(7)_their fourth cousins but somehow manage to select as friends the people who_(8)_our kin.” The study_(9)_found that the genes for smell were something shared in friends but not genes for immunity.Why this similarity exists in smell genes is difficult to explain,for now,_(10)_,as the team suggests,it draws us to similar environments but there is more_(11)_it.There could be many mechanisms working together that _(12)_us in choosing genetically similar friends_(13)_”functional Kinship”of being friends with_(14)_! One of the remarkable findings of the study was the similar genes seem to be evolution_(15)_than other genes Studying this could help_(16)_why human evolution picked pace in the last30,000years,with social environment being a major_(17)_factor. The findings do not simply explain people’s_(18)_to befriend those of similar_(19)_backgrounds,say the researchers.Though all the subjects were drawn from a population of European extraction,care was taken to_(20)_that all subjects, friends and strangers,were taken from the same population. 1.[A]when[B]why[C]how[D]what 【答案】[D]what 【解析】该题考查的是语法知识。根据句子结构和选项的特点，可以判断出空格处应填
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2015年全国硕士研究生入学统一考试 数学二试题及答案解析 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)下列反常积分中收敛的是 (A) (B) (C) (D) 【答案】D。 【解析】题干中给出4个反常积分，分别判断敛散性即可得到正确答案。 ； ； ； ， 因此(D)是收敛的。 综上所述，本题正确答案是D。 【考点】高等数学—一元函数积分学—反常积分 (2)函数在(-∞,+∞)内 (A) (B)有可去间断点 (C)有跳跃间断点 (D)有无穷间断点 【答案】B 【解析】这是“”型极限，直接有 , 在处无定义， 且所以是的可去间断点，选B。 综上所述，本题正确答案是B。
【考点】高等数学—函数、极限、连续—两个重要极限 (3)设函数().若 (A) (B) (C) (D) 【答案】A 【解析】易求出 再有 于是，存在此时. 当，， = 因此，在连续。选A 综上所述，本题正确答案是C。 【考点】高等数学—函数、极限、连续—函数连续的概念，函数的左极限和右极限 (4)设函数在(-∞,+∞)内连续，其 二阶导函数的图形如右图所示， 则曲线的拐点个数为 A O B (A) (B) (C) (D) 【答案】C 【解析】在(-∞,+∞)内连续，除点外处处二阶可导。的可疑拐点是的点及不存在的点。 的零点有两个，如上图所示，A点两侧恒正，对应的点不是拐点，B点两侧，对应的点就是的拐点。
虽然不存在，但点两侧异号，因而() 是的拐点。 综上所述，本题正确答案是C。 【考点】高等数学—函数、极限、连续—函数单调性，曲线的凹凸性和拐点 (5)设函数满足则与依次是 (A) (B) (C) (D) 【答案】D 【解析】先求出 令 于是 因此 综上所述，本题正确答案是D。 【考点】高等数学-多元函数微分学-多元函数的偏导数和全微分 (6)设D是第一象限中由曲线与直线围成的平面区域，函数在 D上连续，则 (A) (B) (C) (D) 【答案】 B
2015考研数学三真题及答案解析
2015年全国硕士研究生入学统一考试数学（三）试题 一、选择题:18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)设是数列,下列命题中不正确的是： (A) 若,则(B) 若, 则 (C) 若,则(D) 若,则 (2)设函数在内连续,其2阶导函数的图形如下图所示,则曲线的拐点个数为： (A) (B) (C) (D) (3)设,函数在上连续,则 (A) (B) (C) (D) (4)下列级数中发散的是： (A) (B) (C) (D)
(5)设矩阵,.若集合，则线性方程组有无穷多解的充分必要条件为： (A) (B) (C) (D) (6)设二次型在正交变换为下的标准形为，其中 ，若，则在正交变换下的标准形为： (A) (B) (C)(D) (7)若为任意两个随机事件,则: (A)(B) (C) (D) (8)设总体为来自该总体的简单随机样本, 为样本均值,则 (A) (B)(C)(D) 二、填空题：914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) (10)设函数连续，若则 (11)若函数由方程确定，则 (12)设函数是微分方程的解，且在处取得极值3，则 (13)设阶矩阵的特征值为，其中E为阶单位矩阵，则行列式
(14)设二维随机变量服从正态分布，则 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. (15) (本题满分10分) 设函数，，若与在是等价无穷小，求 的值. (16) (本题满分10 分) 计算二重积分，其中 (17) (本题满分10分) 为了实现利润的最大化，厂商需要对某商品确定其定价模型，设为该商品的需求量，为价格，M C 为边际成本，为需求弹性. (I) 证明定价模型为； (II) 若该商品的成本函数为，需求函数为，试由（I）中的定价模型确定此商品的价格. (18) (本题满分10分) 设函数在定义域上的导数大于零，若对任意的，由线在点处的切线与直线及轴所围成区域的面积恒为4，且，求的表达式. (19) (本题满分 10分) (I) 设函数可导，利用导数定义证明 (II) 设函数可导，，写出的求导公式.
2015年考研英语一翻译真题解析
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2015年考研英语一真题及解析
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