**Also, both Anthony (cheesebucket) and I worked together on this post but someone *cough*Anthony*cough* has poor penmanship so in order to spare you the trouble of trying to decipher it, here it is in my writing.
This quadrant discusses how to find ALL trig. functions when you are given one trig. functions and quadrant, using the identities from concept 1. It allows us to apply these fundamental identities to more difficult concepts such as this one.
What must the viewer pay special attention to in order to understand?
You first have to decide the quadrant in which the values lie in by using ASTC quadrants, this will only determine the signs (very important!!) But also please remember you must using reciprocal, ratio, or Pythagorean identities to find the remaining values (don't rely on just SOHCAHTOA, we will use this to find our values.) AND you can only have ONE unknown trig function within solving the identity no matter what identities you use. Also make sure that you properly rationalize all your answers!!