1. The problem statement, all variables and given/known data Prove using the formal definition of a limit that Lim x→4 x2 = 16 2. Relevant equations |f(x)-L| and |x-c| Using epsilon/delta definition. 3. The attempt at a solution I've got that |x2-16| = |x-4||x+4| I'm also pretty sure only |x-4| matters, since it is the same as |x-c|. What would delta be? Since there's no coefficient of x to factor out, would delta = epsilon? Another note: I really have no idea what I'm doing. I've based all my work off of prior examples, I don't understand how to "prove" the limit using the above information.