Answer:
R = √2
α = π/4 or 45°
Step-by-step explanation:
R cos(2n + α)
Use angle sum formula:
R [cos(2n) cos α − sin(2n) sin α]
R cos(2n) cos α − R sin(2n) sin α
Match the coefficients:
R cos α = 1
R sin α = 1
Divide:
tan α = 1
α = π/4 or 45°
Solve for R:
R cos(π/4) = 1
R / √2 = 1
R = √2
