Chapter 4 - Polynomials - Review Exercises: Chapter 4 - Page 299: 56

$16y^6-40y^3+25$

Using $(a+b)^2=a^2+2ab+b^2$ or the square of a binomial, the product of the given expression, $ (4y^3-5)^2 ,$ is \begin{array}{l}\require{cancel} (4y^3)^2+2(4y^3)(-5)+(-5)^2 \\\\= 16y^6-40y^3+25 .\end{array}