x^9+x^6+x^3-3=(X^9-1)+(X^6-1)+(X^3-1)=(X^3-1))(X^6+X^3+1)+(X^3-1)(X^3+1)+(X^3-1)=(X^3-1)(X^6+1+X^3+X^3+1+1)=(X^3-1)(X^6+2X^3+3)=(X-1)(X^2+X+1)(X^6+2X^3+3)
