$a^3 + b^3 = (a + b)(a^2 - ab + b^2)$ $a^3 - b^3 = (a - b)(a^2 + ab + b^2)$

Go ! Factoriser: !

 $a^3 + 1 =$ $(a-1)(a^2+a+1)$ $16+2x^3y^3 =$ $2 (2+xy(4-2xy+x^2y^2))$