Question

(a-b)(a-b)-(a+b)(a-b) is equal to?

Answer 1

(a-b) (a-b) - (a+b) (a-b)
=(a-b) ^2-a^2+b^2
=a^+b^2-2ab-a^2+b^2
=2b^2-2ab

Answer 2

(a-b)(a-b)-(a+b)(a-b)

=>a^2 + b^2 - 2ab -(a^2 - b^2)

a^2 + b^2 - 2ab -a^2 + b^2

[* a^2 gets neutralized]

=2  b^2 - 2 a b