Double-Angle Identities

In this lesson, we will continue to learn about trigonometric identities. Here, we will focus on the double-angle identities, the product-to-sum identities, and the sum-to-product identities. We will see examples where we need to use the double-angle identities to find the values for our six trigonometric functions. Additionally, we will use our product-to-sum and sum-to-product identities to find an exact value for a trigonometric function.