Question

Factor x^4-4

Answer 1

This is a difference of squares problem
Remember that : a^2-b^2: (a+b)(a-b), which means that
x^4 can be thought of as (x^2)^2 and 4 can be written as 2^2. This means that we are actually dealing with: (x^2)^2-2^2 which can be factored as: (x^2+2)(x^2-2)