关于x的二次方程(m-1)x^2+(2m-4)x+m=0有两个正实数根
==>(1)m-1≠0,(2)△≥0,(3)(4-2m)/(m-1)>0,(4)m/(m-1)>0
==>(1):m≠1
(2)4(m-2)^2-4m(m-1)≥0
=>m≤3/4
(3)1