Question

I want to fined out that
a^2+b^2
________is equal to?
a+b

Answer 1

(a+b)²-2ab

Explanation:

First we need to factorize (a+b)²

(a+b)² = a² + 2ab + b²

(a+b)² = a²+b²+2ab

Subtract 2ab from both sides

(a+b)² - 2ab = a²+b²+2ab - 2ab

(a+b)²-2ab = a²+b²

Swap;

a²+b² = (a+b)²-2ab

Hence the expression of a² + b² is (a+b)²-2ab