Question

(I know this would be an easy one) how can you say that (a+b)^2 is a^2 +b^2+2ab

Answer 1

We can say that (a+b)^2 = a^2 + 2ab + b2 because

(a+b)^2 means -> (a+b) * (a+b)
= a^2 + ab + ba + b^2
= a^2 +ab + ab + b^2
= a^2 + 2ab +b^2