Trigonometric equations may have multiple solutions that must be found. To solve such an equation: isolate the trigonometric function, use the inverse function to find the first solution, use the unit circle to find a second solution, and use the periodic nature of trig functions to state the general solution accounting for all possibilities. For example, isolate the trig function, use the inverse to find one solution, use the unit circle to find another, and use periodicity to give the full general solution.