Given: 12pq(2p+3q)2−(2p−3q)2
By using the identities,
(a+b)2=a2+2ab+b2(a−b)2=a2−2ab+b2
the denominator can be simplified as
(2p+3q)2−(2p−3q)2=4p2+9q2+12pq−(4p2+9q2−12pq)=4p2+9q2+12pq−4p2−9q2+12pq=24pq
The the given expression becomes,
12pq(2p+3q)2−(2p−3q)2=12pq24pq=12