Question

[-2(m+l+n)]^2
How to open it?

Answer 1

Just do (-2)^2(m+l+n)^2=4(m+l+n)^2 And then apply (a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ac

Answer 2

by using bodmas rule

-2^2(m+l+n)^2

4(m