So, for a different problem, part (c) on the link, I have:
lim x^3 + 2x + 1 = 4, x --> 1
Let ε > and L = 4
|x-1| < δ, |x^3 +2x - 3| < ε
But this one doesn't factor...[EDIT] wait, yes it does (I peeked at the solution, how do I factor this by myself?).
|x-1||x^2 + x + 3| < ε