Trig – Ch. 7-1 Proving Trig Identities Objectives: To understand how to verify an identity.

Trigonometric identities

Class Work Simplify

Proving Identities 1) Start with one side. Pick one side of the equation and write it down. Start with the more complicated side Transform it into the other side.

2) Use known identities. Use algebra and known identities to change the side you started with. Bring fractional expressions to a common denominator. Factor Use fundamental identities to simplify your expression. Use the conjugate

3) Convert sines and cosines. It may be helpful to convert all functions to sines and cosines. 4) Introduce something new 5) Always keep the end in mind

Ex 1. Verify the identity.

Ex 2. Verify the identity

Ex 3. Verify the identity.

Ex 4. Verify the identity.

Class Work 3. 4.

Class Work 5. 6.