## Calculus with Applications (10th Edition)

$(x-y)(x+y)(x^2+y^2)$
RECALL: $a^2-b^2=(a-b)(a+b)$ The given expression can be written as: $(x^2)^2-(y^2)^2$ Factor this expression using the formula above with $a=x^2$ and $b=y^2$ to have: $=(x^2-y^2)(x^2+y^2)$ Factor the first binomial using the same formula with $a=x$ and $b=y$ to have: $=(x-y)(x+y)(x^2+y^2)$