Answer:
θ = πk, 1.318+2πk, 4.965+2πk
Step-by-step explanation:
4sin(2θ) − 2sin(θ) = 0
8sin(θ)cos(θ) - 2sin(θ) = 0
2sin(θ)[4cos(θ)-1] = 0
2sin(θ) = 0
sin(θ) = 0
θ = πk
4cos(θ)-1 = 0
4cos(θ) = 1
cos(θ) = 1/4
θ ≈ 1.318+2πk, 4.965+2πk
Therefore, θ = πk, 1.318+2πk, 4.965+2πk