f(x)+g(x)=1/(x-1) (1)
令x=-x
f(-x)+g(-x)=1/(-x-1) (2)
(1)+(2)两式相加,因为偶函数奇函数
2f(x)=2/(x^2-1),则f(x)=1/(x^2-1)
则g(x)=x/(x^2-1)