sinx cosxxcosxC.
sinxxD. sinxB. 答案C 22.已知广义积分???dx是收敛函数,则k的取值范围是( ) exlnkxA.k?1 B.k?1 C.k?1 D.k?1 答案D 23.设f(x)?e?arcsinx则?cosxf'(sinx)dx?(A.ex?c B.e?x C.e?x?c
D.ex 答案C
24.设函数z?arccotyx,则?2z?x?y?( ) A.x?y2xy(x?y)2 B.x?y4xy(x?y)2 C.y?x4xy(x?y)2 D.y?x2xy(x?y)
答案B
25.交换二次积分次序
?'2x?10dx?xf(x,y)dy?(
)
)
1y31?A.
?dy?00f(x,y)dx??dy?y1122f(x,y)dx
B.
?dy?01y1?22yf(x,y)dx
31C. ?1dy?y1?22dx??dy?f(x,y)dx
001yD.
?3y0dy?y?1f(x,y)dx
22 答案A
26.下列关系正确的是( ) A. d?f(x)dx?f(x)
B. d?f(x)dx?df(x) C. d?f(x)dx?f(x)dx D. d?f(x)dx?f(x)?C 答案B
27.设f(x)为连续函数,则?x?f(t)dt)?等于( aA. f(x)?f(a) B. f(a)?f(x) C. f(x) D. f(a) 答案C
28.设函数z?y3x,则
?z?y等于( ) A. y3xlny B. 3y3xlny C. 3xy3x D. 3xy3x?1
)
答案D
sin2mx29.lim等于( )
x??2x2 A. 0 B .
m 2m2 C.
2D. ? 答案A
30.lim(n?n?n)?( )
n??2A.0 B.
1 2C.1 D.不存在 答案B
ln(1?x)n?( ) 31. limx?0xA.n B.
1 nnC.e D.e 答案A 32.lim(x??1nx?12x)?( ) x?2A.e B.e C.1 D.e 答案D
?2212x2?5x?6?( ) 33.lim2x?3x?4x?3A.
12 B.1
C.54 D.?
答案A
x2sin134.limxx?2?( ) x??3A.0 B.1
C.13 D.?
答案C
35.limn2?nsinxn??2n2?3ncosx?( ) A.不存在 B.
12 C.1 D.2
答案B
??1?36.要使函数f?x??1?x??x?a?bxA.0,1
B.
112,2 C.12,任意数 D.0,任意数 答案C
37.limsin(x2?4)x?2x?2?( ) A.12 B.8 C.10 D.4
答案D
x?0在x=0处连续,则a,b的值分别为(x?0 )
38.limsinx??1ln(1?x) xA.1 B.0 C.2 D.不存在 答案B 39.设y?in1?sinx,则y??( )
1?sinxA.ln(1?sin2x)
B.2sinxcos2x
C.sinxcos2x D.?secx 答案D
40.limex?cosx?2?0ln(1?2x)?(xA.1 B.2 C.
12 D.不存在 答案C 41.lim1?cosxx?0xln(1?x)?( )A.1 B.2
C.12 D. ?12
答案D 42.lim(3x?1xx?0?1)?( )A.-3 B.-2 C.e?3 D.e?2
)