[(x^2-6x)/(x+2)+2]/[(x^2-4)/(x^2+4x+4)]
=[(x^2-6x+2x+4)/(x+2)]/[(x^2-4)/(x+2)^2]
=[(x^2-4x+4)/(x+2)]/[(x-2)(x+2)/(x+2)^2]
=[(x-2)^2/(x+2)]/[(x-2)/(x+2)]
=(x-2)^2/(x+2)*(x+2)/(x-2)
=x-2
=2+根号3-2
=根号3