(3-2x)/(x-3)-(2+mx)/(3-x)=-1
都乘以x-3得：3-2x+(2+mx)=-x+3
解得：x=-2/(m-1)
方程无解,∴x=-2/(m-1)是增根x=3
即：-2/(m-1)=3
解得：m=1/3