(a+b)(a+b)
(a+2b)(a+b)
(x+y)(x-y)
(a+2b)(a+b)
(x+y)(x-y)
-
Take each term in the first bracket and multiply it by each term in the second bracket. So we have. a squared. plus ab plus ba plus b squared. Or a squared plus 2ab plus b squared. Also the second one is a squared plus 3ab plus 2b squared. And the third one is x squared minus y squared.