Tag Archives: trigonometric identities

Trigonometry – Sum and Difference Formulas of Sine and Cosine

By | September 15, 2016

Sum and Difference Formulas of Sine and Cosine In this tutorial student learn how to verify a trigonometric equation using trigonometric identities like the difference formula for sine and cosine. Virginia Standards of Learning (SOL) T.5 Key Points of Knowledge Sum and Difference Formulas cos (α + β) = cos (α) cos (β) – sin (α)… Read More »