Chapter 4 - Polynomials - 4.7 Polynomials in Several Variables - 4.7 Exercise Set - Page 283: 6

(b) the product of the sum and difference of the same two terms.

RECALL: (1) $(a+b)^2$ is a square of a binomial (2) $(a-b)(a+b)$ is the product of the sum and difference of the same two terms The given expression is in the same form as the one in part (2) above. Thus, the given expression is the product of the sum and difference of the same two terms.