x>0,h(x)=f(x)/x=mx-1+(2m-1)/xh'(x)=m-(2m-1)/x^2函数h(x)在区间[1,2]上是增函数即x∈[1,2],h'(x)=m-(2m-1)/x^2≥0恒成立即 mx^2≥2m-1当m=0时,0≥-1,成立当 m>0时,mx^2∈[m,4m],需m≥2m-1 =>m≤1当mm≥-1/2综上所...