solve: cos2theta - 3 cos theta + 2 / sin2theta = 1 Share with your friends Share 15 Tanveer Sofi answered this We have cos2θ-3cosθ+2sin2θ=1⇒cos2θ-3cosθ+2=sin2θ⇒cos2θ-3cosθ+2=1-cos2θ As sin2θ=1-cos2θ⇒2cos2θ-3cosθ+1=0⇒2cos2θ-2cosθ-cosθ+1=0⇒2cosθcosθ-1-1cosθ-1=0⇒2cosθ-1cosθ-1=0⇒2cosθ-1=0 or cosθ-1=0⇒cosθ=12 or cosθ=1⇒θ = 60° or θ = 0°rejectedSo, θ = 60° 34 View Full Answer
