x1+x2=3-m得（x1+x2)²=(3-m)²x1*x2=m(x1-x2)²=（x1+x2)²-4x1*x2 =(3-m)²-4m =m²-10m+9∵二根差绝对值小于2√5∴0≤m²-10m+9≤20解得-1≤m≤1或9≤m≤11...