(2-x)^3=(2-x)(4-4x+x^2)=8-12x+6x^2-x^3=8-x^3-6x(2-x)
8-x^3=(2-x)^3+6x(2-x)
=(2-x)(4-4x+x^2+6x)=(2-x)(4+2x+x^2)