方程有实根,判别式△≥0
△=(4m-3)^2-4(2m-1)(1-m)
=24m^2-36+13
=24(m-3/4)^2-1/2≥0
(m-3/4)^2≥3/144
m≥3/4+√3/12或m≤3/4-√3/12
两根为负根,则两根之和0
由韦达定理,得
(4m-3)/(1-2m)3/4或m0
解得
1/2