高等数学(一)密押试卷
一、选择题(1~10小题,每小题4分,共40分.在每小题给出的四个选项中,只有一项是符合题目要求的) 1.lim(1?)x??1x2x?()
A.e B.e C.e D.e
2?1
?211??D lim(1?)2x??lim(1?)x?=e2.
x??xx??x??2.设函数f(x)可导,且limx?02x?2,则f?(1)?()
f(1?x)?f(1)A.2 B.1 C.
1 2D.0
C f?(1)?limx?0f(1?x)?f(1)?xlimx?01xf(1?x)?f(1)?1. 23. 设y?e?5x,则dy?() A.?5e?5xdx B.?e?5xdx C.e?5xdx D.5e?5xdx
A 因为y?e?5x,y???5e?5x,所以dy??5e?5xdx. 4.函数y?ex+arctanx在区间[-1,1]上() A.单调减少 B.单调增加 C.无最大值
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D.无最小值 B 因y??ex+1]上单调增加.
25.xcosxdx?
1?0处处成立,于是函数在(-∞,+∞)内都是单调增加的,故在[-1,21+x?A.?2sinx?C B.?21sinx2?C 22C.2sinx?C D.
1sinx2?C 22?xcosxdx?D 6.
1122cosxdx?sinx2?C(C为任意常数). ?22?1?1(3x2?sin5x)dx?()
A.-2
B.-1 C.1 D.2 D
?1?1(3x?sinx)dx??3xdx??sinxdx?2?3xdx?0?2x?1?1025121512310?2.
d0t2tedt?() 7.
dx?xA.xe B.?xe C.xe?x2x2x2
D.?xeB
?x2d0t2dxt2x2tedt??tedt??xe. ??x0dxdx?z2?() 8.设z?xy,则?xA.xy
B.2xy C.x
2 2
D.2xy+x2
B 因为z?x2y,故
?z?(x2)?y?2xy. ?x9.级数
?(?1)nn?1?k(k为非零常数)() n2A.绝对收敛 B.条件收敛 C.发散
D.收敛性与k的取值有关
??kkun?(?1)2?0.?un??(?1)n2?kA n??时,
nnn?1n?1n1,显然级数k?2nn?1?1收?2nn?1?敛,故
?un收敛,即?(?1)nn?1n?1??k绝对收敛. 2n10.微分方程y???2y??x的特解应设为() A.Ax B.Ax+B C.Ax+Bx D.Ax+Bx+C
C 因f(x)?x为一次函数,且特征方程为r?2r?0,得特征根为r1?0,r2?2.于是特解应设为y?(Ax+B)x?Ax?Bx.
二、填空题(11~20小题,每小题4分,共40分)
?2222sin2x?3,则a? .
x?0ax2sin2x2sin2x22?lim=?3,则a?. lim3x?0axax?02xa3x?212.函数f(x)?的间断点为 .
x?2x?22 函数f(x)?在x?2处无定义,故x?2为f(x)的间断点.
x?2x?113.曲线y?的铅直渐近线方程为 .
2x?111.设lim111x?1x?1x?? 当x??时,lim的铅直渐近线. ??,故x??是y?12222x?1x??2x?1214.过点M(1,2,3)且与平面2x?y?z?0平行的平面方程为 .
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2x?y?z?3 由题意知,所求的方程为2(x?1)?(y?2)?z?3?0,即2x?y?z?3.
15.设函数f(x)???2x?a,x?0,在x?0处连续,则a? .
?3,x?0x?0x?03 因为函数f(x)在x?0处连续,则limf(x)?lim(2x?a)?a?f(0)?3. 16.曲线y?x2?x在点(1,0)处的切线斜率为 .
1 因为y?x2?x,y??2x?1,y?(1)?1,故曲线y?x2?x在点(1,0)处的切线斜率为1. 17.幂级数
?(?1)n?1n?1?1nx的收敛半径R? . 2n?11 R?limn??anan?112(n?1)2?1n?1?lim?lim?1.
n??n??1n2?1(n?1)2?122?2z18.设z?ln1?x?y,则? . ?x?y?2xy?z12xx22z?ln1?x?y ,则,???222222222(1?x?y)?x1?x?y1?x?y21?x?y?2z?x?2y?2xy故. ???x?y(1?x2?y2)2(1?x2?y2)219.设区域D?(x,y)x?y?4,则
?22?1dxdy? . ??4Dπ
1111dxdy?dxyd=S??π=4π. D????44D44D2y20.设函数z?xe,则全微分dz= . 2xeydx?x2eydy z?x2ey,
?z?z?2xey,?x2ey, ?x?y则dz=?z?zdx?dy?2xeydx?x2eydy. ?x?y三、解答题(21~28题,共70分.解答应写出推理、演算步骤)
21.(本题满分8分)
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ex?x?1求lim. x?0xex?x?1ex?1?lim?0. 解:limx?0x?0x122.(本题满分8分)
设曲线方程为y?ex?x,求y?x?0以及该曲线在点(0,1)处的法线方程.
解:y??ex?1, 则y?x?0=2.
1(x?0), 2曲线在点(0,1)处的法线方程为y?1??即x?2y?2?0. 23.(本题满分8分)
exdx. 计算?1?exex1xxdx?d(1?e)?ln(1?e)?C(C为任意常数). 解:?xx?1?e1?e24.(本题满分8分)
设l是曲线y?x?3在点(1,4)处的切线,求由该曲线、切线l及y轴围成的平面图形的面积S.
解:y?x?3,y??2x, 则切线l的斜率为k?2, 故切线l的方程为y?2x?2.
11312?S???(x?3)?(2x?2)dx?(x?x?x)?. ?0?033122225.(本题满分8分)
y函数y?y(x)由方程e?sin(x?y)确定,求dy.
y解:将e?sin(x?y)对x求导, 有e?y??cos(x?y)(1?y?),
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y