4x/(x^3+2x^2+x)+5x/(x^3+2x^2-5x)+3/2=0 4/(x^2+2x+1)+5/(x^2+2x-5)+3/2=0设y=x^2+2x+1=(x+1)^24/y+5/(y-6)+3/2=08/y+10/(y-6)+3=03y^2=48y^2=16y=4 y=-4(不合题意,舍去)(x+1)^2=4x+1=±2x=1 x=-3经检验,x=1 x=3都是原方程的解