Question

How do you simplify `(5+sqrt3)(5-sqrt3)`?

Answer 1

This is of the form `(a+b)(a-b)` with `a=5` and `b=sqrt(3)`

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

So

`(5+sqrt(3))(5-sqrt(3)) = 5^2-(sqrt(3))^2 = 25 - 3 = 22`