Question

expand the square of a binomial (r-q)^2

Answer 1

$(r-q)^2=r^2-2rq+q^2$

Explanation

remember the rule to expand the square of a binomial

$(a-b)^2=a^2-2ab+b^2$

Step 1

apply the rule,

let

a=r

b=q

replace

$\begin{gathered} (a-b)^2=a^2-2ab+b^2 \\ (r-q)^2=r^2-2rq+q^2 \end{gathered}$

I hope this helps you