3/(x-2)-4/(x-1)=1/(x-4)-2/(x-3)[3(x-1)-4(x-2)]/(x-2)(x-1)=[(x-3)-2(x-4)]/(x-4)(x-3)(-x+5)/(x-2)(x-1)=(-x+5)/(x-4)(x-3)∴-x+5=0或者(x-2)(x-1)=(x-4)(x-3)即：x=-5或者x²-3x+2=x²-7x+12解得：x1=5 x2=2.5经检验，都是原方程的根。
