1)m=0时,x-2=0, 得:x=2
m<>0时,delta=(2m-1)^2-4m(m-2)=4m^2-4m+1-4m^2+8m=4m+1
当m>=-1/4时,有实根;
当m<-1/2时,无实根
2)x1+x2=(2m-1)/m=2-1/m, x1x2=(m-2)/m=1-2/m
(x1-3)(x2-3)=x1x2-3(x1+x2)+9=1-2/m-6+3/m+9=4+1/m=5m
即:5m^2-4m-1=0
(5m+1)(m-1)=0
得:m=-1/5, 1
(2m-1)^2-4m(m-2)
=4m^2-4m+1-4m^2+8m
=4m+1>0有实数根
x1x2-3(x1+x2)+9=5m
x1x2=(m-2)/m
x1+x2=(2m-1)/m
(m-2)/m-3(2m-1)/m+9=5m
m-2-6m+3+9m=5m^2
5m^2-4m-3=0
m=(4+根号76)/10