The LCM is the lowest expression that both p and q divide into.
LCM (p,q) = a^3b^3
The HCF is the highest common factor of p and q:-
HCF (p,q) = a^2b
HCF(p,q) * LCM (p,q) = a^3b^3 * a^2b = a^5b^4 and
pq = a^2b^3 * a^3b = a^5b^4
Therefore HCF(p,q) * LCM(p,q) = pq