Answer:
5π/4, 7π/4
Step-by-step explanation:
The sign of the sine tells you the angles of interest are in the 3rd and 4th quadrants. cos(θ) = ±√(1/2) tells you the reference angle is π/4 radians. The angles of interest are ...
π +π/4 = 5π/4
2π -π/4 = 7π/4
