This document contains trigonometric equations to solve: find the values of x for which √3 sec x + 2 = 0 over an unknown interval, find the values of x for which csc x - 6 = 0 over an unknown interval, and find the values of x for which 9cos(x) tan(x) + 3tan(x) = 0 over the interval [180°, 360°]. It also contains the equation 2cos(x) sin(x) = cos(x).