(a-b)^3-3(a-b)^2== (a-b)^2(a-b-3)= (a-b)(a-b)(a-b-3)
(x+y)^3+2x(x+y)^2= (x+y)^2(x+y+2х)=(x+y)(x+y)(3x+y)
(a-b)^3-3(a-b)^2== (a-b)^2(a-b-3)= (a-b)(a-b)(a-b-3)
(x+y)^3+2x(x+y)^2= (x+y)^2(x+y+2х)=(x+y)(x+y)(3x+y)