[3/(x-1)-1/(x+1)]×(x²-1)/x=[3(x+1)/(x²-1)-(x-1)/(x²-1)]×(x²-1)/x=(2x+4)/(x²-1)×(x²-1)/x=(2x+4)/x将x=1/2代入得原式=(1+4)/(1/2)=10愿对你有所帮助!