`sec^2 (x) - 4sec(x) = 0` Use inverse functions where needed to find all solutions of the equation in the interval `0,2pi)`.
Borys Shumyatskiy | Certified Educator
So sec(x)=0 or sec(x)=4.
sec(x)=1/cos(x) and it is never zero. It is =4 when cos(x)=1/4. There are two solutions on (0, 2pi): arccos(1/4) and 2pi-arccos(1/4).
They are approximately 75.5° and 284.5°.