Question

Factor completely. x^4 - 9.

Answer 1

`(x^2+3)(x^2-3)`

Explanation:

Since both are perfect squares use the difference of squares formula
`a^2-b^2=(a+b)(a-b)` with a =
`x^(2)` and b = 3

=
`(x^2 +3)(x^2-3)`