The problem statement, all variables and given/known data Find all solutions of inverse sine (-1/2). Angles lie between 0 and 2∏. The attempt at a solution I know it sounds very simple, but i must be having some of the basics wrong, as i can't figure out the second solution. I used the calculator (in radian mode) to find inverse of sin (-1/2) which gives -∏/6 Since the value of inverse sin (-1/2) must be between 0 and 2∏, i went with the automatic reflex of adding 2∏ to that answer which gives 11∏/6 but then i checked the answer and there is a second solution! And i have no idea how to get that second solution. I need to know a simple, yet consistent method that i can use across all problems of that type, if that's possible.