Answer
$a^2-2ab+b^2$;
minus;
product of the first and second terms;
plus
Work Step by Step
RECALL:
$(a-b)^2=a^2-2ab+b^2.$
Thus, the missing expressions/words in the given statements are
$a^2-2ab+b^2$;
minus;
product of the first and second terms;
plus.
