Learning Resources

Investigation 7A: Is the Calculator Defective? & Investigation 7B: The Distance Formula and Compound Angle Identities

Part (b)

To develop the identity for sin(a - b), you will use the following facts:

• sin(a + b) = sina cosb + cosa sinb

• sin(a - b) = sin(a + (-b))

• cos(b) = cos(-b)

• sin(-b) = -sin(b)