Question

Factorize each of the following algebraic expression:
p²q² − 6pqr + 9r²

Answer 1

$$\begin{gathered} p^2{q}^2-6pqr+9r^2 \\ =(pq{)}^2-2\times pq\times 3r+(3r{)}^2 \\ =(pq-3r{)}^2 \\ =(pq-3r\left)\right(pq-3r) \end{gathered}$$