The first thing you want to do when you run into a trig limit is…Don’t Freak Out. Most people hit a trig problem, and just looking at it they immediately believe they are going to have a hard time with it. You do need to know your Unit Circle and you Trig Identities, especially how to rewrite all trig functions in terms of sine and cosine. Those areas are just like factoring, if you are going to be successful in calculus you must know the basic Unit Circle and Trig Identities.

Once you have that knowledge most limits of trig equation problems can be broken into three main categories of problems; Simplify then Plug it in, Sine Limit Identity, or Cosine Limit Identity. We are going to look first at the Simplify then Plug it in method.