Factorize:
(l + m)2 – 4lm
Given,
By using the formula (a + b)2 = a2 + b2 + 2ab
We get,
(l + m)2 – 4lm = (l2 + m2 + 2lm) – 4lm
= l2 + m2 + 2lm – 4lm
= l2 + m2 – 2lm
= (l)2 + (m)2 - 2×l×m
= (l – m)2