17、?18、
??1xx?1'2dxt?x?1???2tt(t21?1)dt?2???1t21?1dt?2arctant??1??2
?z?x2?f1?f2?y;
'?z?x?y?f11?(?1)?f12?x?f2?yf21?(?1)?f22?x
''''''22''''''?''''???f11?(x?y)f12?xyf?f2
19、原式???Dsinyydxdy?1?10dy?yy2sinyydx??10(1?y)sinydy
?(y?1)cosy14?x?210??40cosydy?1?sin1
11?x?24020、f(x)??1??14??(?1)n?0n(x?2)4nn,(?2?x?6)
21、证明:令t???x,?xf(sinx)dx???(??t)f(sin(??t)dt?0????0(??t)f(sint)dt
???f(sinx)dx?0???0xf(sinx)dx
故?xf(sinx)dx?0??2??0f(sinx)dx,证毕.
??0xsinx1?cos2xdx???2?sinx1?cos20x'dx???2'arctan(cosx)?0??24
22、等式两边求导的xf(x)?2x?f(x)即f(x)?xf(x)??2x且f(0)??1,p??x,
x22q??2x, qe?pdx?pdx???x22,e?pdx?e2?e22,e??pdxx2?e2,
?dx???2xq?x2dx?2e?x2?x2
x2所以f(x)?(2e2?C)e2?2?Cex22,由f(0)??1,
解得C??3,f(x)?2?3e2
23、设污水厂建在河岸离甲城x公里处,则
M(x)?500x?7004022?(50?x),0?x?50,
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M?500?700?'12?402(x?50)2?(50?x)2?0
解得x?50?5006(公里),唯一驻点,即为所求.
2005年江苏省普通高校“专转本”统一考试高等数学参考答案
1、A 2、C 3、D 4、A 5、A 6、C 7、2 8、e?1 9、11、?dy?01y?12?2 10、5
?1?yf(x,y)dx 12、(?1,1)
13、因为F(x)在x?0处连续,所以limF(x)?F(0),
x?0limF(x)?limx?0f(x)?2sinxxx?0?limf(x)?f(0)xx?0?2?f(0)?2?6?2?8,
'F(0)?a,故a?8.
dy2(y)tcost?cost?tsintdy?1dt????t,???csct. 14、2'dxdx?sint?sintdxxtdy''dt15、原式
??tan2xtanxsecxdx??(sec2x?1)dsecx??sec2xdsecx?secx?213sec3x?secx?C.
16、原式?xarctanx?4121210??21x1?x1002dx??4?12?1d(1?x)1?x20
???z?x??ln(1?x)ln2
?417、
?cosx?f1,
'?z?x?y2?cosx(f12?2y)?2ycosxf12
''''18、l??5,2,1?,B??4,?3,0?,AB??1,?4,2?
ij2?4k1??8,?9,?22? 2??l?AB?51平面点法式方程为:
8(x?3)?9(y?1)?22(z?2)?0,即8x?9y?22z?59.
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19、f(x)?x23(12?x?11?x)?x26?11?x2?x23?11?x
?(?1)n?n??1??n?1?x,收敛域为?1?x?1. 3n?0?2?x?220、y?'1x?y?exx,通解为
11xxdx?Cee?xdx??? y?eexdx?C?????x?xx???
因为y(1)?e,e?e?C,所以C?0,故特解为y?exx.
21、证明:令f(x)?x3?3x?1,且f(?1)?3?0,f(1)??1?0,f(?1)?f(1)?0, x???1,1?,由连续函数零点定理知,f(x)在(?1,1)上至少有一实根.
22、设所求函数为y?f(x),则有f(2)?4,f'(2)??3,f''(2)?0. 由y''?6x?a,y''(2)?0得a??12,即y''?6x?12.
因为y''?6x?12,故y'?3x2?12x?C1,由y'(2)??3,解得C1?9. 故y?x?6x?9x?C2,由y(2)?4,解得C2?2. 所求函数为:y?x?6x?9x?2. 23、(1)S?3232?11220ydy?216y310?16
121(2)Vx???20 (1?2x)dx??(x?x)2?40?24、解:积分区域D为:1?y?u,y?x?u
uxu(1)F(u)???Df(x)d???1dx?f(x)dy?1'?1(x?1)f(x)dx;
(2)F(u)?(u?1)f(u),F(2)?(2?1)f(2)?f(2)?1.
'
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2006年江苏省普通高校“专转本”统一考试高等数学参考答案
1、C 2、B 3、C 4、C 5、C 6、A 7、2 8、f(x0) 9、?1 10、1 11、exy(ysinx?cosx) 12、1
1?4313、原式?lim3x?112dydxyx't'txx?12?23
1??11?t2t2214、??t2,
dydx22(?dydx'xt)'1?22t1?t2?1?t4t2
1?t15、原式???1?lnxd(1?lnx)?23?3(1?lnx)2?C
??16、原式??20xdsinx?xsinx2220?2?2xsinxdx?02?24?2?2xdcosx
0??2??4?2xcosx20?2?cosxdx?20?4?2
y?y?17、方程变形为y'????,令p?则y'?p?xp',代入得:xp'??p2,分离变量得:
xx?x?y2??1pdp?2?x1dx,故
1p?lnx?C,y?xlnx?C?.
?n18、令g(x)?ln(1?x),g(0)?0,g(x)?'?(?1)n?0xdx?n?n?0(?1)nn?1xn?2,
?故f(x)??n?0(?1)nn?1xn?2,?1?x?1.
ij?1?3k1?2i?3j?k 119、n1?1,?1,1?、n2?4,?3,1?,l?n1?n2?34x?322'2直线方程为
?z?y?y?13?z?21'.
20、?xf,
?z?y?x2?2xf2?x(f21?2x?f22?y)?2xf2?2xf21?xyf22.
2'''''3''2'' 39
21、令f(x)?3x?x3,x???2,2?,f'(x)?3?3x2?0,x??1,f(?1)??2,f(1)?2,
3f(2)??2,f(?2)?2;所以fmin??2,fmax?2,故?2?f(x)?2,即3x?x?2.
22、y'?2x?y,y(0)?0
通解为y?(?2x?2)?Cex,由y(0)?0得C?2,故y??2x?2?2ex. 23、(1)S?4?2?2(8?x?x)dx?822643
(2)V???(y)2dy???(8?y)2dy?16?
0424、??f(x)dxdy?Dtt??f(x)g(t)???0??a?t0dx?f(x)dy?t?f(x)dx
00ttt?0t?0
(1)limg(t)?limt?0t?0?t0f(x)dx?0,由g(t)的连续性可知a?g(0)?limg(t)?0
t?0(2)当t?0时,g'(t)?f(t),
g(h)?g(0)h当t?0时,g(0)?lim综上,g'(t)?f(t).
'h?0?lim?h0f(x)dxh?limf(h)?f(0)
h?0h?0
2007年江苏省普通高校“专转本”统一考试高等数学参考答案
1、B 2、C 3、C 4、A 5、D 6、D 7、ln2 8、1 9、2? 10、
1yxy232
11、dx?dy 12、y''?5y'?6y?0
13、解:lime?x?1xtanxxyxx?0?lime?x?1x2xx?0?lime?12xxxx?0?limexx?02?12.
x14、解:方程e?e?xy,两边对x求导数得e?e?y'?y?xy',故
ydydx?y'?e?ye?xy.
又当x?0时,y?0,故
dydxx?0?1、
dydx22x?0??2.
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