Question

How do you find the solutions of `secx = (-2sqrt3)/3`?

Answer 1

f(x) = sec x = 1/cos x = -2(sqr.3)/3 --> cos x = -(sqr.3)/2.
Trig conversion table gives x = 5Pi/6.
Trig unit circle gives another arc x that has the same cos value: 7Pi/6.
Within the interval (0, 2Pi), there are 2 answers: 5Pi/6 and 7Pi/6