Answer:
θ = π n + π/2 for n element Z
Step-by-step explanation:
Solve for θ:
1 + 2 cos(2 θ) + cos^2(2 θ) = 0
Write the left hand side as a square:
(cos(2 θ) + 1)^2 = 0
Take the square root of both sides:
cos(2 θ) + 1 = 0
Subtract 1 from both sides:
cos(2 θ) = -1
Take the inverse cosine of both sides:
2 θ = 2 π n + π for n element Z
Divide both sides by 2:
Answer: θ = π n + π/2 for n element Z