x-1分子x+1-x^2-1分之4=1(x+1)/(x-1)-4/(x-1)(x+1)=1(x+1)²-4=x²-1x²+2x+1-4=x²-1x²+2x-3-x²=-12x=-1+32x=2x=1因为x=1原方程无意义，所以原方程无解
