Problems:
Trigonometric identities and equations
Q1. Prove the identity
cos3Θ = 4cos^3Θ- 3cosΘ
Q2. Prove the identity:
(cos3Θ - cos7Θ)/(sin7Θ + sin3Θ) = tan2Θ
Q3. Solve the equation, giving answer in radians in the range 0 to 2 ∏
sin(2Θ) -1 = cos(2Θ)