2016年考研数学(二)真题及答案解析完整版
2016年考研数学二真题及答案解析
(1
)设
33
123cos1,ln1,11axxaxxax.当0x时,以上3个无
穷小量按照从低阶到高阶的排序是()
(A)
123,,.aaa(B)
231,,.aaa
(C)
213,,.aaa(D)
321,,.aaa
【答案】(B)
【解析】当0x时
2
121
~1cosxxxa
65
3
2~1lnxxxa
xxa
31
~11
31
3
故从低阶到高级顺序:
132,,aaa,选B.
(2)已知函数
21,1
ln,1xx
fx
xx
,则
fx的一个原函数是()
22
221,11,1
ln1,1.ln11,1.
1,11,1
ln11,1.ln11,1.xxxx
AFxBFx
xxxxxx
xxxx
CFxDFx
xxxxxx
【答案】(D)
【解析】由原函数必连续,故A,C排除.又1x时,
xxxln'11ln,故选D.
(3
)反常积分①1
0
21
,xedx
x
②1
2
01
xedx
x
的敛散性为()
(A)①收敛②收敛.(B)①收敛②发散.
(C)①收敛②收敛.(D)①发散②发散.
【答案】(B)
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.
【解析】
110|1
011
0
2
xxedxe
x收敛,
eedxe
xxx1|1
011
02发散.
(4)设函数()fx
在
,内连续,其导函数的图形如图所示,则()
(A)函数()fx有2个极值点,曲线()yfx有2个拐点.
(B)函数()fx有2个极值点,曲线()yfx有3个拐点.
(C)函数()fx有3个极值点,曲线()yfx有1个拐点.
(D)函数()fx有3个极值点,曲线()yfx有2个拐点.
【答案】(B)
【解析】由
xf'两个零点左右都反号,故极值点有两个,
又拐点是
xf'的极值点,故拐点有三个,选(B).
(5)设函数()(1,2)
ifxi具有二阶连续导数,且''
0()0(1,2)
ifxi,若两条曲线
()(1,2)
iyfxi在点
00(,)xy处具有公切线()ygx
,且在该点处曲线
1()yfx的曲率
大于曲率
2()yfx的曲率,则在
0x的某个邻域内,有()
12()()()().Afxfxgx
21()()()().Bfxfxgx
12()()()().Cfxgxfx
21()()()().Dfxgxfx
【答案】(A)
【解析】如图所示,答案为(A).
(6)已知函数(,)xe
fxy
xy
,则()
''''
''''()0.()0.
().().xyxy
xyxyAffBff
CfffDfff
【答案】(D)
【解析】
2'
yxeyxe
fxx
x
,
2'
yxe
fx
y
故
''
2.xx
xyexye
fff
xyxy
(7)设,AB是可逆矩阵,且A与B相似,则下列结论错误的是()
(A)TA与TB相似.
(B)1A
与1B
相似.
(C)TAA与TBB相似.
(D)1AA与1BB相似.
【答案】(C)
【解析】此题是找错误的选项.由A与B相似可知,存在可逆矩阵,P使得1PAPB,则
11
11111111
11111111(1)()()~,A
(2)()~
(3)()~,
TTTTTTTTPAPBPAPBAB
PAPBPAPBABB
PAAPPAPPAPBBAABBD
故()不选;
,故()不选;
故()不选;
此外,在(C)中,对于111()TTPAAPPAPPAP,若1=PAPB
,则
1()TTTTPAPB,而1TPAP
未必等于TB,故(C)符合题意.综上可知,(C)为正确选
项.
(8)设二次型222
123123122313(,,)()222fxxxaxxxxxxxxx的正负惯性指数分别
为1,2,则()
(A)1.a
(B)2.a
(C)21.a
(D)1a或2.a
【答案】(C)
【解析】考虑特殊值法,当0a时,
123122313(,,)222fxxxxxxxxx,
其矩阵为011
101
110
,由此计算出特征值为2,1,1,满足题目已知条件,故0a成立,
因此(C)为正确选项.
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)曲线3
2
2arctan1
1x
yx
x
的斜渐近线方程为.【答案】
2
xy【解析】
2
2
2arctan1
limlim1.
1
xxx
yx
k
xxx
21arctan
1lim1arctan
1limlim
2
22
23
x
xxxx
xx
xyb
xxx故渐近线为.
2yx
(10)极限
2112
limsin2sinsin
nn
n
nnnn
.
【答案】sin1cos1【解析】由
1
0
12
1sin1
sinlim1
sinlimxdxx
nni
ni
nni
iIn
inn
in
1
1
0
0cos|cossin1cos1.xxxdx
(11)以2xyxe
和2yx
为特解的一阶非齐次线性微分方程为.
【答案】22yyxx
【解析】令微分方程为
xqyxPy
则
xqexxPexxqxxPx
xx22
22
故21,2.Pxqxxx
(12)已知函数
fx
在
,
上连续,且2
012x
fxxftdt
,则当2n
时,
0nf.
【答案】225
【解析】由
22212'
xfxxfxxf
则
40,10'
ff
则
xfxf'''12,故
5210''
xf
xfxf'''''2,故
52022'''''
fxf
以此类推,得
521
nnxf,故
'''''22025.fxf
(13)已知动点P在曲线3xy上运动,记坐标原点与点P
间的距离为l.若点P
的横坐标
时间的变化率为常数
0v,则当点P
运动到点
1,1
时,l对时间的变化率是_________.
【答案】
022v
【解析】令
tytxP,,则
txty3
又
tytxl22
则
tytxtytytxtx
dtdl
22''
又
0'2'
0'33,vtxtxtyvtx
则00
03
22.
2vvdl
v
dt
2016考研英语二完整版真题及答案解析
2016考研公共课英语二完整版真题及答案解析下载
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)
Happy people work differently. They’re more productive, more creative, and
willing to take greater risks. And new research suggests that happiness might
influence__1__firm’s work, too.
Companies located in places with happier people invest more, according to a
recent research paper.__2__, firms in happy places spend more on R&D (research
and development). That’s because happiness is linked to the kind of longer-term
thinking__3__for making investments for the future.
The researchers wanted to know if the__4__and inclination for risk-taking that
come with happiness would__5__the way companies invested. So they compared
2016年考研英语二真题及解析
2016研究生入学统一考试试题及答案解析(英语二)
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)
Happy people work differently. They’re more productive, more creative, and willing to take greater risks. And new
research suggests that happiness might influence__1__firm’s work, too.
Companies located in places with happier people invest more, according to a recent research paper.__2__, firms in
happy places spend more on R&D (research and development). That’s because happiness is linked to the kind of longer-term
thinking__3__for making investments for the future.
The researchers wanted to know if the__4__and inclination for risk-taking that come with happiness would__5__the
way companies invested. So they compared U.S. cities’ average happiness__6__by Gallup polling with the investment
2016年考研数学二真题及答案解析
2016年全国硕士研究生入学统一考试数学二试题答案
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
1(
cos1)axx
,3
2l
n(1)axx
,3
31
1ax
.当0x
时,以上3个无
穷小量按照从低阶到高阶的排序是()
(A)
1
23,,aaa
.(B)
2
31,,aaa
.
(C)
2
13,,aaa
.(D)
3
21,,aaa
.
【答案】(B)
【解析】当0x
时,
2
11
(cos1)~
2axxx
,5
3
6
2ln(1)~axxx,3
31
11~
3axx
所以3个无穷小量按照从低阶到高阶的排序是
2
31,,aaa
,故选B.
2、已知函数2(
1),1,
()
ln,1,xx
fx
xx
则()fx
的一个原函数是
(A)2
(1),1.
()
(ln1),1.xx
Fx
xxx
(B)2
(1),1.
()
(ln1)1,1.xx
Fx
xxx
(C)2
(1),1.
()
(ln1)1,1.xx
Fx
xxx
(D)2
(1),1.
()
(ln1)1,1.xx
Fx
xxx
【答案】(D)
【解析】2
(1)1
()()
ln1xx
Fxfxdx
xxxCx
,
()Fx需连续,(1)(1)FF
1C
3
、反常积分1
0
21
xedx
x
①
,1
+
2
01
xedx
x
②
的敛散性为
(A)①
收敛,②
收敛.(B)①
收敛,②
发散.
(C)①
发散,②
收敛.(D)①
发散,②
发散.
【答案】(B)
【解析】11
1110020011(limlim
)1
xxxxx
x
xedxedeee
xx
,收敛
111111
+
2
00
0011
(limlim)1lim
0xxxxxx
x
xxedxedeeee
xx
,
发散
故选B.
2016年考研英语二真题答案及解析
2016年全国硕士研究生招生考试英语(二)答案详解
SectionIUseofEnglish
一、文章总体分析及结构这是一篇议论文,选自2016年《哈佛商业评论》,全文共358词。文章围绕快乐与公司投资之间的关系展开。
首先提出研究表明快乐不仅影响人们的行为方式,也有可能会影响公司的运营方式;接着介绍了研究者们是如何证
明这一观点的;最后指出,作者也认为快乐对公司投资有所影响。
二、语篇精读Happypeopleworkdifferently.They’remore
productive,morecreative,andwillingtotakegreaterrisks.
Andnewresearchsuggeststhathappinessmight
influence__1__firm’swork,too.快乐的人工作起来会有所不同。他们更多产,更有创
造力,也愿意去冒更大的风险。近期的一项研究表明快乐
也可能会影响公司的运营(1)方式。
词汇详解:productive富有成效的;多产的takerisk····冒···风险;承担风险
creative(人)有创造力的suggest表明;暗示
influuence影响
长难句分析:Andnewresearchsuggeststhathappinessmightinfluencehowfirm’swork,too.
本句的主干是newresearchsuggeststhat...,that后引导宾语从句,其中happiness是宾语从句的主语,另外,这
个宾语从句中还包含how引导的宾语从句。Companieslocatedinplaceswithhappierpeopleinvest
more,accordingtoarecentresearchpaper.__2__,firmsin
happyplacesspendmoreonR&D(researchanddevelopment).That’sbecausehappinessislinkedtothekind
2016年考研(数学二)真题试卷(题后含答案及解析)
2016年考研(数学二)真题试卷 (题后含答案及解析)
题型有:1. 选择题 2. 填空题 3. 解答题
选择题下列每题给出的四个选项中,只有一个选项符合题目要求。
1. 设a1=x(cos一1),a2=,a3=一1.当x→0+时,以上3个无穷小量按照从低阶到高阶的排序是__________.
A.a1,a2,a3
B.a2,a3,a1
C.a2,a1,a3
D.a3,a2,a1
正确答案:B
2. 已知函数f(x)=则厂(x)的一个原函数是___________.
A.F(x)=
B.F(x)=
C. F(x)=
D. F(x)=
正确答案:D
3. 反常积分①,②的敛散性为___________.
A.①收敛,②收敛
B.①收敛,②发散
C.①发散,②收敛
D.①发散,②发散
正确答案:B
4. 设函数厂(x)在(一∞,+∞)内连续,其导函数的图形如图所示,则_________.
A.函数f(x)有2个极值点,曲线y=f(x)有2个拐点
B.函数f(x)有2个极值点,曲线y=f(x)有3个拐点
C.函数f(x)有3个极值点,曲线y=f(x)有1个拐点
D.函数f(x)有3个极值点,曲线y=f(x)有2个拐点
正确答案:B
5. 设函数fi(x)(i=1,2)具有二阶连续导数,且fi(x0),则_________.
A.fx一fy=0
B.fx+fy=0
C.fx-fy=f
D.fx+fx=f
正确答案:D
7. 设A,B是可逆矩阵,且A与B相似,则下列结论错误的是_______.
A.AT与BT相似
B.A-1与B-1相似
C.A+AT与B+BT相似
D.A+A-1与B+B-1相似
正确答案:C
8. 设二次型f(x1,X2,X3)=a()+2x1x2+2x2x3+2x1x3的正、负惯性指数分别为1,2,则___________.
A.a>1
B.a<一2
2016年英语二考研真题及答案(完整版)
第 1 页 共 18 页 2016年英语二考研真题及答案(完整版) 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) Happy people work differently. They’re more productive, more creative, and willing to take greater risks. And new research suggests that happiness might influence__1__firm’s work, too. Companies located in places with happier people invest more, according to a recent research paper.__2__, firms in happy places spend more on R&D (research and development). That’s because happiness is linked to the kind of longer-term thinking__3__for making investments for the future. The researchers wanted to know if the__4__and inclination for risk-taking that come with happiness would__5__the way companies invested. So they compared U.S. cities’ average happiness__6__by Gallup polling with the investment activity of publicly traded firms in those areas. __7__enough, firms’ investment and R&D intensity were correlated with the happiness of the area in which they were__8__.But is it really happiness that’s linked to investment, or could something else about happier cities__9__why firms there spend more on R&D? To find out, the researchers controlled for various__10__that might make firms more likely to invest – like size, industry, and sales – and for indicators that a place was__11__to live in, like growth in wages or population. The link between happiness and investment generally__12__even after accounting for these things. The correlation between happiness and investment was particularly strong for younger firms, which the authors__13__to “less codified decision making process” and the possible presence of “younger and less__14__managers who are more likely to be influenced by sentiment.” The relationship was__15__stronger in places where happiness was spread more__16__.Firms seem to invest more in places where most people are relatively happy, rather than in places with happiness inequality. __17__ this doesn’t prove that happiness causes firms to invest more or to take a longer-term view, the authors believe it at least__18__at that possibility. It’s not hard to imagine that local culture and sentiment would help__19__how executives think about the future. “It surely seems plausible that happy people would be more forward-thinking and creative and__20__R&D more than the average,” said one researcher. 1. [A] why [B] where [C] how [D] when 2. [A] In return [B] In particular [C] In contrast [D] In conclusion 3. [A] sufficient [B] famous [C] perfect [D] necessary 4. [A] individualism [B] modernism [C] optimism [D] realism 5. [A] echo [B] miss [C] spoil [D] change 6. [A] imagined [B] measured [C] invented [D] assumed 7. [A] Sure [B] Odd [C] Unfortunate [D] Often 8. [A] advertised [B] divided [C] overtaxed [D] headquartered 9. [A] explain [B] overstate [C] summarize [D] emphasize 10. [A] stages [B] factors [C] levels [D] methods 11. [A] desirable [B] sociable [C] reputable [D] reliable 12. [A] resumed [B] held [C]emerged [D] broke
2016年考研英语二真题答案及解析 2
2016年全国硕士研究生招生考试英语(二)答案详解
SectionIUseofEnglish
一、文章总体分析及结构这是一篇议论文,选自2016年《哈佛商业评论》,全文共358词。文章围绕快乐与公司投资之间的关系展开。
首先提出研究表明快乐不仅影响人们的行为方式,也有可能会影响公司的运营方式;接着介绍了研究者们是如何证
明这一观点的;最后指出,作者也认为快乐对公司投资有所影响。
二、语篇精读Happypeopleworkdifferently.They’remore
productive,morecreative,andwillingtotakegreaterrisks.
Andnewresearchsuggeststhathappinessmight
influence__1__firm’swork,too.快乐的人工作起来会有所不同。他们更多产,更有创
造力,也愿意去冒更大的风险。近期的一项研究表明快乐
也可能会影响公司的运营(1)方式。
词汇详解:productive富有成效的;多产的takerisk····冒···风险;承担风险
creative(人)有创造力的suggest表明;暗示
influuence影响
长难句分析:Andnewresearchsuggeststhathappinessmightinfluencehowfirm’swork,too.
本句的主干是newresearchsuggeststhat...,that后引导宾语从句,其中happiness是宾语从句的主语,另外,这
个宾语从句中还包含how引导的宾语从句。Companieslocatedinplaceswithhappierpeopleinvest
more,accordingtoarecentresearchpaper.__2__,firmsin
happyplacesspendmoreonR&D(researchand
development).That’sbecausehappinessislinkedtothe
2016考研数学一真题及答案解析(完整版)
2016考研数学(一)真题完整版
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)若反常积分011badxxx收敛,则( )
11111111AabBabCaabDaab且且且且
(2)已知函数21,1ln,1xxfxxx,则fx的一个原函数是( )
22221,11,1ln1,1ln11,11,11,1ln11,1ln11,1xxxxAFxBFxxxxxxxxxxxCFxDFxxxxxxx
(3)若22222211,11yxxyxx是微分方程ypxyqx的两个解,则qx( )
2222313111xxAxxBxxCDxx
(4)已知函数,0111,,1,2,1xxfxxnnnn,则( )
(A)0x是fx的第一类间断点 (B)0x是fx的第二类间断点
(C)fx在0x处连续但不可导 (D)fx在0x处可导
(5)设A,B是可逆矩阵,且A与B相似,则下列结论错误的是( )
(A)TA与TB相似 (B)1A与1B相似
(C)TAA与TBB相似 (D)1AA与1BB相似
(6)设二次型222123123121323,,444fxxxxxxxxxxxx,则123,,2fxxx在空间直角坐标下表示的二次曲面为( )
(A)单叶双曲面 (B)双叶双曲面 (C)椭球面 (C)柱面
2016年考研数学二真题与解析
Page1of142016年考研数学二真题与解析
一、选择题1—8小题.每小题4分,共32分.
1.当
0x
时,若)(lnx21
,1
1)cos(x
均是比x
高阶的无穷小,则
的可能取值范围是()
(A)),(2
(B)),(21
(C)),(1
21
(D)),(
21
0
【详解】xx221~)(ln
,是阶无穷小,
2
11
21
1xx~)cos(是
2
阶无穷小,由题意可知
121
所以
的可能取值范围是),(21
,应该选(B).
2.下列曲线有渐近线的是
(A)xxysin
(B)xxysin2
(C)
xxy1
sin
(D)
xxy1
2sin
【详解】对于
xxy1
sin,可知1
xy
xlim且01
xxy
xxsinlim)(lim
,所以有斜渐近线xy
应该选(C)
3.设函数)(xf
具有二阶导数,xfxfxg)())(()(110
,则在],[10
上()
(A)当0)('xf
时,)()(xgxf
(B)当0)('xf
时,)()(xgxf
(C)当0)(xf
时,)()(xgxf
(D)当0)(xf
时,)()(xgxf
【分析】此题考查的曲线的凹凸性的定义及判断方法.
【详解1】如果对曲线在区间],[ba
上凹凸的定义比较熟悉的话,可以直接做出判断.显然
xfxfxg)())(()(110
就是联接))(,()),(,(1100ff
两点的直线方程.故当0)(xf
时,曲线是凹
的,也就是)()(xgxf
,应该选(D)
【详解2】如果对曲线在区间],[ba
上凹凸的定义不熟悉的话,可令
xfxfxfxgxfxF)())(()()()()(110
,则010)()(FF
,且)(")("xfxF
,故当
0)(xf
时,曲线是凹的,从而010)()()(FFxF
,即0)()()(xgxfxF
,也就是Page2of14)()(xgxf
2020年考研数学二真题及答案解析
2020考研数学二真题及解析完整版
来源:文都教育
一、选择题:1~8小题,第小题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,请将选项前的字母填在答题纸指定位置上.
1.0x
,下列无穷小量中最高阶是()
A.
2
0e1dx
tt
B.
3
0ln1+dx
tt
C.sin
2
0sindx
tt
D.1cos
3
0sindx
tt
答案:D
解析:A.
23
2
001~
3xx
tx
edttdtB.35
3
22
002
ln1~
5xx
tdttdtxC.sin
223
001
sin~
3xx
tdttdtxD.231
1cos
3
22
00sin~xx
tdttdt
251
22
02
5x
t
5
2
25211
52102xx
2.1
1ln|1|
()
(1)(2)x
xex
fx
ex
第二类间断点个数()
A.1
B.2
C.3
D.4
答案:C
解析:0,2,1,1xxxx
为间断点1
111
1
0000ln|1|ln|1|ln|1|
lim()limlimlim
(1)(2)222x
x
xxxxexexexe
fx
exxx
0x为可去间断点
1
1
22ln|1|
lim()lim
(1)(2)x
x
xxex
fx
ex
2x为第二类间断点
1
1
11ln|1|
lim()lim0
(1)(2)x
x
xxex
fx
ex
1
1
11ln|1|
lim()lim
(1)(2)x
x
xxex
fx
ex
1x为第二类间断点
1
1
11ln|1|
lim()lim
(1)(2)x
x
xxex
fx
ex
1x
为第二类间断点3.1
0arcsin
d
(1)x
x
xx
A.2π
4B.2π
8C.π
4D.π
8
答案:A解析:
1
0arcsin
d
(1)x
x
xx
令ux
,则
原式=1
220arcsin
·2d
(1)u
uu
uu1
20
2
0
2
2
2
