原式=[(x²+2x)/(x²+4x+4)]÷[(2x²-8)/(3x+6)]÷[1/(x²-4)]
=[x(x+2)/(x+2)²]÷{2(x+2)(x-2)/[3(x+2)]}÷{1/[(x+2)(x-2)]}
=[x/(x+2)]÷[2(x-2)/3]×(x+2)(x-2)
=[x/(x+2)]×3/[2(x-2)]×(x+2)(x-2)
=3x/2