
Bradford T. answered 11/05/20
Retired Engineer / Upper level math instructor
csc(2x) = 1/sin(2x) = -2
Solve for sin(2x):
sin(2x) = -1/2
Since this is negative, 2x will be in the 3rd and 4th quadrants.
Need to find all angles of sin that have a value of -1/2. For example sin(7π/6) = -1/2.
So 2x = 7π/6 --> x = 7π/12. Look at the trigonometry wheel to find the rest of the angles with sin(θ) = -1/2 and then divide that radian angle by 2.
Maybe they want the negative angles too, sin(-π/6) = -1/2