奇函數(shù),f(-x)=-f(x)
所以(ax^2+1)/(-bx+c)=-(ax^2+1)/(bx+c)
所以1/(-bx+c)=-1/(bx+c)
-bx+c=-bx-c
c=0
f(x)=(ax^2+1)/bx
f(1)=(a+1)/b=2
a=2b-1
f(2)=(4a+1)/2b<3
(4a+1)/2b-3<0
(4a-6b+1)/2b<0
[4(2b-1)-6b+1]/2b<0
(2b-3)/2b<0
所以2b(2b-3)<0
0b是整數(shù),所以b=1
a=2b-1
所以a=1,b=1,c=0
f(x)=(x^2+1)/x