f（x）=x+1/x-1(x不等于正负1)则f(x)乘f(-x)=?f(-x)+f(x)=?
问题描述：
f（x）=x+1/x-1(x不等于正负1)则f(x)乘f(-x)=?f(-x)+f(x)=?
答
f(x)=(x 1)/(x-1)f(-x)=(-x 1)/(-x-1)=(x-1)/(x 1)f(x)乘f(-x) = [(x 1)/(x-1)]X[(x-1)/(x 1)] = 1f(x)加f(-x) = [(x 1)/(x-1)] [(x-1)/(x 1)]让分母一样,(x 1)x(x-1) = (x^2)-1[(x 1)/(x-1)] [(x-1)/(x 1)] = [(x^2...