Question

Find the product of each of the following (x+a)(x-a), (x+a)^2 (x-a)^2

Answer 1

ANSWER

• (x+a)(x-a) = x² - a²

,

• (x+a)² = x² + 2ax + a²

,

• (x-a)² = x² - 2ax + a²

EXPLANATION

For the first product we can use the difference of two squares rule:

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

Then, for the other two we just have to apply the perfect square rule:

$(a\pm b)^2=a^2\pm2ab+b^2$