Question

How do you factor `g^4-1`?

Answer 1

`(g+1)(g-1)(g^2+1)`

Explanation:

We are looking at the sum of two squares

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

So applying that rule we get
`(g^2-1)(g^2+1)`

We can also see that the `(g^2-1)` term is also a sum of two squares so it now looks like

`(g+1)(g-1)(g^2+1)`