Question

factorisation :-
rule (a^2 -b^2 ) = (a+b)(a-b)
1. (l+m) ^2 - (l- m)^2​

Answer 1

Answer:

(l + m)2 – (l – m)2

= [(l + m) + (l – m)][(l + m) – (l – m)]

= (2l)(2m) = 4lm