Precalculus (6th Edition) Blitzer

$a^2+2ab+b^2$; squared; product of the first and second terms; squared
RECALL: $(a+b)^2=a^2+2ab+b^2.$ Thus, the missing words/expression in the given statement (in order) are $a^2+2ab+b^2$; squared; product of the first and second terms; squared.