(x+1)/(x-1)=3(x+1)/(x-1)-3=0[(x+1)-3(x-1)]/3(x-1)=0(x+1)-3(x-1)=0x+1-3x+3=0-2x=-4x=2经检验x=2是方程的根
x+1=3x-34=2xx=2经检验，x=2是原方程根
