Answer
(a) "$\forall p, q\in R$, if $pq=0$ then $p=0\vee q=0$"
(b) "$\forall p, q\in R$, if $p\ne0\wedge q\ne0$ then $pq\ne0$ "
(c) "For any real numbers $p$ and $q$, if $p\ne0$ and $q\ne0$, then $pq\ne0$"
Work Step by Step
(a) Let $p$ and $q$ be two real numbers, the zero product property states that: "$\forall p, q\in R$, if $pq=0$ then $p=0\vee q=0$"
(b) We can write a contrapositive as:
"$\forall p, q\in R$, if $p\ne0\wedge q\ne0$ then $pq\ne0$ "
(c) We can write an informal version as:
"For any real numbers $p$ and $q$, if $p\ne0$ and $q\ne0$, then $pq\ne0$"
