Why is 3tan^2θ - 1 = 0 equal to -pi/6 and pi over 6?
My first steps were to isolate the θ and I got + and - sqrt 3 / 3
Looking on my unit circle I got four answers (pi/6),(5pi/6),7pi/6), and (11pi/6)
however my textbook says that the answers are -pi/6 and pi over 6... why?