Calculating limits that have a divide-by-zero issue (specifically 0/0 form) involves a few algebra tricks to evaluate the limit. There might be a hole in the graph, but you can still determine the limit of the function at that hole by finding a way to cancel the factor in the denominator causing the divide-by-zero. I go through quite a few examples, since there a lot of curve balls that your teacher (or the AP exam writers!) can throw at you. I hope this helps a lot! Comment and grab the PDF of the blank notes below.
PDF: Limits Boot Camp #4