## Elementary Algebra

$(x+2y)(x^2-2xy+4y^2)$
Using $a^3+b^3=(a+b)(a^2-ab+b^2)$, or the factoring of the sum of $2$ cubes, the factored form of the given expression, $x^3+8y^3 ,$ is \begin{array}{l}\require{cancel} (x+2y)[(x)^2-x(2y)+(2y)^2] \\\\= (x+2y)(x^2-2xy+4y^2) .\end{array}