## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$(4x^2+y^2)(2x+y)(2x-y)$
Using $x^2-y^2=(x+y)(x-y)$ or the factoring of the difference of 2 squares, then the factored form of the given expression, $16x^4-y^4 ,$ is \begin{array}{l} (4x^2+y^2)(4x^2-y^2) \\\\= (4x^2+y^2)(2x+y)(2x-y) \end{array}