1-cos²θ-2cosθ+1/4=0. cos²θ+2cosθ-5/4=0. 4cos²θ+8cosθ-5=0. (2cosθ-1)(2cosθ+5)=0. cosθ=1/2. θ=2nπ±π/3
The general solution of sin²θ - 2cosθ + 1/4 = 0 is:
Verified 30 May 2026.
θ = 2nπ ± π/3
θ = 2nπ ± π/6
θ = nπ ± π/3
θ = nπ + (-1)ⁿπ/6
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