Sum and Difference Identities for Sine and Tangent

Learn about sum and difference identities for sine and tangent in this 26-minute video lesson. Explore formulas for sin(A + B), sin(A - B), tan(A + B), and tan(A - B). Practice finding exact values for trigonometric functions, such as sin 165° and tan pi/12. Discover how to simplify expressions using difference identities and verify trigonometric identities. Apply these concepts to determine function values and quadrants for combined angles. Gain a comprehensive understanding of these important trigonometric concepts through clear explanations and practical examples.

Introduction.
Formulas for sin(A + B) and sin(A - B).
Finding the exact value of sin 165°.
Simplifying using difference identity for sine.
Formulas for tan(A + B) and tan(A - B).
Finding the exact value of tan pi/12.
Verifying a trigonometric identity with the sum identity for sine and cosine.
Finding sin(θ + β), tan(θ + β) and the quadrant of θ + β.