2015考研数学极限必做100题
岭南大学-财务总结
1 如果limx→x0fx存在,则下列极限一定存在的为
(A)
limx→x0fxα (B)limx→x0fx (C)limx→x0lnfx
(D)
limx→x0arcsinfx
2
设fx在x=0处可导,f0=0,则limx→0x2fx-2fx3x3 =
(A)
-2f'0
(B
-f'0
(C)
f'0
(D)0
3.设fx,gx连续x→0时,fx和gx为同阶无穷小则x→0时,0xfx-tⅆt为
01xgxtⅆt
的
(A)低阶无穷小 (B)高阶无穷小
(C)等价无穷小 (D)同阶无穷小
4.设正数列an
满足limn→∞0anxnⅆx =2 则limn→∞an=
(A)2
(B)1 (C)0 (D)12
5.x→1时函数x2-1x-1ⅇ1x-1的极限为
(A)2
(B)0 (C)∞ (D)不存在,但不为
∞
6.设fx 在x=0的左右极限均存在则下列不成立的为
(A)limx→0+fx = limx→0-f-x (B)
limx→0fx2 = limx→0+fx
(C)limx→0fx =
limx→0+fx (D)limx→0fx3 = limx→0+fx
6. 极限limx→∞ⅇsin1x-11+1xα-1+1x=A≠0的充要条件为
(A)α>1 (B)α≠1 (C)α>0 (D)和α无关
7.
.已知limx→∞
x21+x-ax-b=0,其中a,b为常数则a,b的值为
(A)a=l ,b=1
(B)a=-1 ,b=1
(C)a=1,b=-1
(D a=-1,b=-1
8.
当
x→0
时下列四个无穷小量中比其他三个更高阶的无穷小为
(A)x2
(B)1-cosx (C)1-x2-1 (D)x-tanx
9.
已知xn+1=xnyn ,yn+1=12xn+yn ,x1=a>0,y1=b>0
(a 则数列
xn和yn
(A)
均收敛同一值(B)均收敛但不为同一值 (C)均发散 (D)无法判定敛散
性
10.
设α>0,β≠0,limx→∞x2α+xα1α-x2=β则α,β为
11. 若
limx→x0fx+gx存在,limx→x0fx-gx不存在,则正确的为
(A)limx→x0fx不一定存在
(B)limx→x0gx不一定存在
(C)limx→x0f2x-g2x 必不存在
(D)limx→x0fx不存在
12. 下列函数中在
1,+∞无界的为
(A)fx=x2sin1x2
(B)fx=sinx2+lnx2x
(C)fx=xcosx+x2ⅇ-x
(D)fx=arctan1xx2
13. 设fx连续limx→0fx1-cosx
=2且x→0时0sin2xftⅆt为x的n阶无穷小
则n=
(A)3
(B)4 (C)5 (D)6
14.
当x→0时下列四个无穷小中比其他三个高阶的为
(A)tanx-sinx
(B)1-cosxln1+x
(C)1+sinxx-1
(D)0x2arcsintⅆt
15. 设x表示不超过x的最大整数,则y=x-x是
(A)无界函数 (B)单调函数 (C)偶函数 (D)周期函数
16. 极限limx→∞x2x-ax+bx=
(A)1
(B)ⅇ (C) ⅇa-b (D)ⅇb-a
17.
函数
fx=x2-xx2-11+1x2的无穷间断点的个数为
(A) 0
(B) 1 (C) 2 (D) 3
18.
如果limx→01x-1x-aⅇx=1,则a=
(A) 0
(B) 1 (C) 2 (D) 3
19.
函数fx=x-x3sinπx的可去间断点的个数为
(A) 1
(B) 2 (C) 3 (D)无穷多个
20. 当x→0+时,与x等价的无穷小量是
(A) 1-ⅇx
(B) ln1+x1-x
(C) 1+x-1 (D)
1-cosx
21.设函数fx=1ⅇxx-1-1 ,则
(A)
x=0,x=1都是fx的第一类间断点
(B)x=0,x=1都是fx的第二类间断点
(C)x=0是fx的第一类间断点,x=1是fx的第二类间断点
(D)x=0是fx的第二类间断点,x=1是fx的第一类间断点
22 limn→∞
lnn1+1n21+2n2…1+nn2等于
(A)12ln2xⅆx (B)
212lnxⅆx (C) 212 ln1+xⅆx (D) 12ln21+xⅆx
23.若limx→0sin6x+xfxx3=0,则limx→06+fxx2为
(A)0 (B)6 (C)36
(D)∞
24.对任意给定的ε∈(0,1),总存在正整数N,当n≥N时,恒有“xn-a≤2ε”
是数列收敛于a的
(A)充分必要条件
(B)充分非必要条件
(C)必要非充分条件
(D)非充要条件
25.设函数fx=limn→∞1+x1+x2n,讨论函数fx的间断点,其结论为
(A) 不存在间断点 (B)存在间断点x=0
(C)存在间断点x=1
(D)存在间断点x=-1
26. . limn→∞tanπ4+2nn=
27.
xsinln1+3x-sinln1+1x =
28.
已知limx→∞3xfx=limx→∞4fx+5 则limx→∞xfx=
29.
在0,1上函数fx=nx1-xn的最大值记为Mn 则limn→∞Mn =
30. 设k、L、δ>0则limx→0δk-x+1-δL-x-1x =
→+∞arcsinx2+x-x =
32. limx→0
0x3sint+t2cos1tⅆt1+cosx0xln1+tⅆt =
→+∞1+2x+3x1x+sinx =
34. α~β(x→a)则limx→aβαβ2β2-α2 =
.limx→00xtsinx2-t2ⅆt1-cosxln1+2x2 =
→0+ⅇx-1-x1lnx =
有连续的导数f0=0,f'0=6,则limx→00x3ftⅆt0xftⅆt3 =
的周期T=3且f'-1=1,则limh→0hf2-3h-f2 =
→∞2nn!nn =
39.设fx在x=1连续且limx→1fx+xx-3x-1
=-3,则
f'1
=
40.极限p=-22limn→∞n2n+x2n
ⅆx
=
→01+tanx1+sinx1x3 =
→+∞lnx1x-1
=
43.x→0时fx=ⅇx-1+ax1+bx为x的3阶无穷小则a=
, b =
44.
极限limx→-∞4x2+x-1+x+1x2+sinx =
→∞1-1221-132⋯1-1n2 =
→+∞6x6+x5-6x6-x5 =
47.
f''x存在f0=f'0=0,f''x>0,ux为曲线fx在x,fx处切线
在x轴的
截距则limx→0xux =
48.
a>0,bc≠0,limx→+∞xaln1+bx-x =c (c≠0)则a= b=
c=
→∞ sinn2+1π =
50.已知x→0时x-a+bcosxsinx为x的5阶无穷小则a = ,b=
limx→0 1+x1x ⅇ 1x =
→+∞0xsintⅆtx =
可导对于∀x∈-∞,+∞有fx≤x2则f'0=
→∞01xn1+xⅆx=
38.如果limx→∞1+xxax=-∞atⅇtⅆt 则a=
39.设x→1+时3x2-2x-1 lnx与x-1n为同阶无穷小则n=
40 .limx→+∞ⅇx1+1x x2 =
→0lnsin2x+ⅇx-xlnx2+ⅇ2x-2x =
42.
x<1时limn→∞1+x1+x2⋯1+x2n=
43.
设极限limx→+∞x5+7x4+2a-x=b(b≠0)则a= b =
44.
limx→∞x-x2ln1+1x =
45.
w=
limx→0
1lnx+1+x2-1ln1+x =
46. 设y=yx由y2+xy+x2-x=0确定满足y1=-1的连续函数
则limx→1x-12yx+1 =
47
.设a1,a2…am为正数(m≥2)则limn→∞a1n+a2n+…+amn1n =
48. fx连续x→0时Fx=0xx2+1-costftⅆt为x3的等价无穷小
则f0=
49. fx连续
f0=0,
f'0≠
0则limx→00x2fx2-tⅆtx301fxtⅆt =
50. fx=x2xsinxttⅆt则limx→0fxx2=
51.
极限limx→∞x2 a1x+1-a1x =
52.
已知fx在x=a可导fx>0 ,n∈N,fa=1,f'a=2
则极限limn→∞
fa+1nfa n=
53. limx→0cot2x-1x2=
54. limx→1lncosx-11-sinπ2x =
55.
如果limx→-∞x2+x+1+ax+b=0
则a=
b=
56. limx→0arcsinxx11-cosx =
57. 已知曲线y=fx在点(0,0)处切线经过点(1,2)则极限
limx→0cosx+0xftⅆt1x2 =
58.
已知fx在x=0邻域内可导且limx→0sinxx2+fxx=2 则f0=
f'0
= limx→0xfx+ⅇx =
59.
limx→01+tanx-1+sinxxlnx+1-
x2
=
60 limx→1lnxln1-x=
61.
limn→∞12+322+523+…+2n-12n =
62.
limx→0a x-1x2-a2ln1+ax = (
a≠0
)
63 .limx→0ⅇ1x+1ⅇ1x-1arctan1x=
64.设fx在a,b连续则limn→+∞01xnfxⅆx =
65.
w=limx→0arcsinx-sinxarctanx-tanx =
66 . limx→0x+3x-3xx2=
67
.limx→+∞1x0x1+t2ⅇt2-x2ⅆt =
68.
limx→0ⅇ2-x+12xx =
69. limx→0
x21+xsinx-cosx =
70.
limn→∞1+12n21+22n2+…+1+n2n21n =
71.
设xn=1n2+1+2n2+22+…+nn2+n2 则limn→+∞xn=
72 .P= limx→0 ln1+ⅇ2xln1+ⅇ1x+ax 存在求p及a的值.
→+∞0x1+t2ⅇt2ⅆtxⅇx2 =
74.
limx→0 1ln1+x2-1sin2x =
75.
limx→+∞ x+ⅇx1x =
76. limx→1
x-xx1-x+lnx =
77.
limn→∞1.3.5.7…2n-12.4.6.8…2n =
78.
limn→∞ 1nnnn-1⋯2n-1 =
79.
极限limx→01-cosx1-3cosx…1-ncosx1-cosxn-1 =
80.
设fx一阶连续可导且f0=0,f'0=1则下列极限limx→01+fx1arcsinx =
81. 函数fx满足f0=0 ,f'0>0则极限limx→0+xfx=
82. limx→+∞x+1+x22x =
83. limx→+∞
π2-arctanx 1lnx =
84.
limx→01-cosxcos2x3cos3xx2 =
85.
函数fx=xln1-x的第一类间断点的个数为
86.
limx→0cotx2sinx =
→+∞ⅇx-2πxarctanxx+ⅇx
=
88. limn→∞
1n2+1+1n2+22+…+1n2+n2 =
89. limx→+∞
x2lnarctanx+1-lnarctanx =
90. limx→+∞ x32x+2-2x+1+x =
91
设x≠0时 limn→∞cosx2cosx4…cosx2n =
92极限w=limx→+∞1+2x1+xarctanx =
93.
limx→0tanx+1-cosxln1-2x+1-ⅇx2 =
94
fx=arcsinx在0,b上用拉格朗日中值定理且中值为ε则limb→0εb =
95 已知曲线y=fx与y=sinx在0,0处相切则limn→∞ 1+f2n n =
96 limn→∞1n2+n+1+2n2+n+2+…+nn2+n+n =
97 limx→+∞ a1x+b1x+c1x3x =
98
极限limx→01+x1x-ⅇx =
99.设fx
在x=1处可导且在(1,f1)处的切线方程为y=x-1,
求极限P =
limx→00x2ⅇtf1+ⅇx2-ⅇtⅆtx2lncosx
100.如果limx→+∞xn+7x4+1m-x=b (n>4
,b≠0)求m,n及b的值
p