f(1/2)=2/5 代入a/2+4b+1=2/5因为f(x)是桐差奇函数,f(-1/2)=-2/5-a/肆轮盯2+4b+1=-2/5解裂和方程组,a=4/5 b=-1/4f(x)=4x/5-1/(4x^2)+1