Answer:
Step-by-step explanation:
Use the half angle formulas
sin(θ/2) = ±√((1 - cosθ)/2)
sin(θ/2) = ±√((1 - (3/5))/2)
sin(θ/2) = ±√((2/5)/2)
sin(θ/2) = ±√(1/5)
knowing θ is in the 4th quadrant, θ/2 will be in the second quadrant where sines are positive.
sin(θ/2) = +√(1/5) = √0.2
