1/9高等数学期末试卷一、填空题(每题2分,共30分)1.函数1142xxy的定义域是
),2[]2,(
2.若函数52)1(2xxxf,则)(xf.解
62x3.________________sinlimxxxx答案:1正确解法:101sinlim1lim)sin1(limsinlimxxxxxxxxxxx4
已知22lim222xxbaxxx,则a_____,b_____
由所给极限存在知,024ba,得42ab,又由23412lim2lim2222axaxxxbaxxxx,知8,2ba5
已知)1)((lim0xaxbexx,则a_____,b_____
)1)((lim0xaxbexx,即01)1)((lim0babexaxxx,1,0ba6.函数0101sin)(xxxxxxf的间断点是x
解:由)(xf是分段函数,0x是)(xf的分段点,考虑函数在0x处的连续性
因为1)0(1)1(lim01sinlim00fxxxxx所以函数)(xf在0x处是间断的,又)(xf在)0,(和),0(都是连续的,故函数)(xf的间断点是0x
设nxxxxy21,则1ny(1)
n2/98.2)(xxf,则__________)1)((xff
答案:2)12(x或1442xx9.函数)1ln(4222yxyxz的定义域为
解:函数z的定义域为满足下列不等式的点集
1040141101042222222222222yxxyyxyxxyyxyxyxz的定义域为:10|),(22yxyx且xy42}10.已知22),(xyyxyxyxf,则),(yxf
解令xyu,xyv,则,22uvuvxy,()()()fxyxyxyxy)(4222),(22vuuuvuvuvuf,22(,)()4xfxyxy11.设22),(yxxxyyxf,则)1,0(xf
)1,0(yf (0,1)0