(ax+1)/(x^2+4x+3)<0的解為x<-4或-3<x<-1,求a的取值范圍.

熱心網友

(ax+1)/(x^2+4x+3)(ax+2)/[(x+1)(x+3)](ax+1)(x+1)(x+3)a=1/4

熱心網友

化為(ax+1)(x+1)(x+3)<0穿根法-4a+1=0a=0.25