How do you derive and apply the Double Angle Formula for sine and cosine in trigonometric integration problems?

Answer 1

Cynthia King

The Double Angle Formulas for sine and cosine are derived from the sum formulas: sin(2θ) = 2sin(θ)cos(θ) and cos(2θ) = cos²(θ) – sin²(θ). These formulas simplify integrals involving trigonometric functions by allowing substitution, facilitating easier integration.