2018年数二考研真题及答案

去百度文库，查看完整内容>内容来自用户:杨晓霞大本营2018年全国硕士研究生入学统一考试数学二试题解析一、选择题：1～8小题，每小题4分，共32分，下列每小题给出的四个选项中，只有一项符合题目要求的，请将所选项前的字母填在答题纸指定位置上.（1）若,则（）【答案】B（2）下列函数中,在处不可导是（）【答案】D（3）设函数，,若在上连续,则（）【答案】D（4）设函数在[0,1]上二阶可导,且,则（A）当时,（B）当时,（C）当时,（D）当时,【答案】D（5）设,,,则的大小关系为（A）（B）（C）（D）【答案】C（6）（A）（B）（C）（D）【答案】C（7）下列矩阵中,与矩阵相似的为【答案】A（8）设为n阶矩阵,记为矩阵的秩，表示分块矩阵，则（A）（B）（C）（D）【答案】A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)曲线在其拐点处的切线方程是______(11)_______(12)曲线在对应点的曲率为（13）设函数由方程确定，则（14）设为3阶矩阵，为线性无关的向量组，若，则的实特征值为【答案】2三、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）求不定积分（16）（本题满分（

去百度文库，查看完整内容>内容来自用户:hahongta2018年全国硕士研究生入学统一考试数学一试题解析一、选择题：1～8小题，每小题4分，共32分，下列每小题给出的四个选项中，只有一项符合题目要求的，请将所选项前的字母填在答．题．纸．指定位置上.（1）下列函数不可导的是（）（A）yxsinx（B）yxsinx（C）ycosx（D）ycosx（2）过点(1,0,0)与(0,1,0)且与zx2y2相切的平面方程为（）（A）z0与xyz1（B）z0与2x2yz2（C）yx与xyz1（D）yx与2x2yz2（3）(1)n2n3（n0(2n1)!）（A）sin1cos1（B）2sin1cos1（C）sin12cos1（D）3sin12cos1（4）设M22(11x)2x2dx，N221xexdx，K2(12cosx)dx，则M,N,K的大小为（）（A）MNK（B）MKN（C）KMN110（5）下列矩阵中，与矩阵011相似的是（）001111（A）011001101（B）011001111（C）010001（D）NMK101（D）010

去百度文库，查看完整内容>内容来自用户:2715749122018年全国硕士研究生入学统考试英语(二)试题2018年全国硕士研究生入学统考试英语(二)试题SectionIUseofEnglishDirections:Readthefollowingtext.Choosethebestword(s)foreachnumberedblankandmarkA,B,CorDontheANSWERSHEET.(10points)rthingsthatwillobviouslyhepainful?Becausehumanshaveaninherentneedto1uncertainty,accordingtoarecentstudyinPsychologicalScience.thatpeoplewill2_rwill3.Inaseriesoffourexperiments,testedstudents'fforttosatisfycuriosity.Forone5_,herclaimedwerefronapreviousexperiment.Thetwist?Halfofthepenswould6anelectricshockwhenclicked.Twenty-sevenstudentsweretoldwhichpenswererigged;anothertwenty-sevenweretoldonlythatsomewereelectrified.7leftaloneintheroom,thestudentswho

去百度文库，查看完整内容>内容来自用户:今生无悔xy本科院校目标院校目标专业姓名.....................................装.......................................订.......................................线.......................................2018年全国硕士研究生统一入学考试数学二试题整理人：中博考研向禹老师xy123@mail.ustc.e.cn题号1-89-14151617181920212223总分分数评卷人一、得分选择题（每题4分,共32分）1.若lim(ex+ax2+)1bxx2=1，则x→011A.a=,b=−1B.a=−,b=−122【解析】由条件得1C.a=,b=12()1D.a=−,b=12()()lnex+ax2+bxln1+ex−1+ax2+bxex−1+ax2+bx0==limx→0limx→0x+x212x2+o(x2)x2=limx→0+ax2+bx=limx→0x2(1+b)x+(12=lim+)ax→0x2+x2o(x2)x2因此b=−1,a=1−.22.下列函数不可导的是A.f(x)=xsinx√B.f(x)=xsinxC.f(x)=cosx()√D.f(x)=cosx【解析】A,B,C可导,D根据导数的定义可得f+′(0)=−12,f−′(0)=1.2−1,3.设函数f(x)=1,x<02−ax,x⩾0,g(x)=xx,−b,x⩽−1−1<x<0,若f(x)

网上有很多

去百度文库，查看完整内容>内容来自用户:yuangehong75922018年考研管理类联考综合英语二真题及答案解析2018年考研管理类联考综合英语二真题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)Why do people read negative Internet comments and do other things that will obviously be painful?Because humans have an inherent need to  1 uncertainty,according to a recent study in Psychological Science. The new research reveals that the need to know is so strong that people will  2 to satisfy their curiosity even when it is clear the answer will  3.In a series of four experiments, behavioral scientists at the University of Chicago and the Wisconsin School of Business tested students' willingness to  4  themselves to unpleasant stimuli in an effort to satisfy curiosity. For one  5 ，each participant was shown a pile of pens that the researcher claimed were from a previous experiment. The twist?Half of the pens would  6  an electric shock when clicked.Twenty-seven students were told which pens were electrified;another twenty-seven were told only that some were electrified. 7 l

去百度文库，查看完整内容>内容来自用户:凯程考研辅导班凯程考研，就是要你考上研究生！2018数三真题刚刚考完，凯程的电话瞬间变成了热线，学员兴奋地汇报他们的考试情况，提到了数学三，两篇作文都是在集训营训练的过的内容。凯程近1-2天发布真题解析视频，凯程艾老师预祝同学们复试顺利。一、选择（1-8题）1、下列函数中，在x0处不可导的是（A）fxxsinx（C）fxcosx（B）fxxsin（D）fxcos1xx2、已知函数fx在0,1上二阶可导，且（A）当fx0时，f（C）当fx0时，f22fxdx0，则010（B）当fx0时，21f021f0210（D）当fx0时，23、设M1x1x22dx，N221x2dxK，1cosxdx，则xe2（A）MNK（B）MKN（C）KMN（D）KNM4、某产品的平均成本函数C(Q)可导，其中Q为产量，若产量为Q0时平均成本最小，则（A）C(Q0)'0(C)（B)C(Q0)'C(Q0)(D)Q0C(Q0)'C(Q0)C(Q0)'Q0C(Q0)1105、下列矩阵中，与矩阵011相似的是001111（A）011

去百度文库，查看完整内容>内容来自用户:pengjiaoer82018年考研英语一真题原文及答案解析完整版2018年全国硕士研究生入学统一考试英语(一)　　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 the ANSWER SHEET. (10 points)　　Trust is a tricky business. On the one hand, it's a necessary condition 1 many worthwhile things: child care, friendships, etc. On the other hand, putting your 2, in the wrong place often carries a high 3.　　4, why do we trust at all? Well, because it feels good. 5 people place their trust in an indivial or an institution, their brains release oxytocin, a hormone that 6 pleasurable feelings and triggers the herding instruct that prompts humans to 7 with one another. Scientists have found that exposure 8 this hormone puts us in a trusting 9: In a Swiss study, researchers sprayed oxytocin into the noses of half the subjects; those subjects were ready to lend significantly higher amounts of money to strangers than were their 10 who inhaled something else.　　11 for us, we also have a sixth sense for dishonesty that may 12 us. A Canadian study found that children as young as 14 months can differentiat

我也在看这道题，好奇怪阿