y=(x-1/x+1)^2y=(x-1)^2/(x+1)^2y(x+1)^2=(x-1)^2(y-1)x^2+2(y+1)x+y-1=0根据一元二次方程公式:x=-1+-2(2y-2)^0.5反函数为f^-1(x)==-1+2(2x-2)^0.5(x>1)
