Answer
$x^3-y^3$
Work Step by Step
$$(x-y)(x^2+xy+y^2)$$ To multiply a binomial by a trinomial, multiply each term in the binomial by each term in the trinomial: $$=(x\times x^2)+(x\times xy)+(x\times y^2)+(-y\times x^2)+(-y\times xy)+(-y\times y^2)$$ $$=x^3+x^2y+xy^2-x^2y-xy^2-y^3$$ Combine like terms: $$=x^3-y^3$$
