x1+x2=-b/a
x1x2=c/a
|x1-x2|=根号[(-b/a)^2-4(c/a)]
=根号[(b^2-4ac)/a]
a+b+c=0 a>b>c
a>0
|x1-x2|=根号(b^2-4ac)/a
b=-a-c a>c 3c0 c>0 c/a1