1. 5.4 Sum and Difference Formulas
In this section students will use sum and difference formulas to evaluate trigonometric functions, verify identities, and solve trigonometric equations.

2. Section 5.4, Sum and Difference Formulas, pg. 368

3. Example 1
Find the exact value of

4. Section 5.4, Sum and Difference Formulas, pg. 368

5. Example 2
Find the exact value of

6. Section 5.4, Sum and Difference Formulas, pg. 368

7. Example 3
Find the exact value of sin(u+v) given
, where and
where

8. Section 5.4, Sum and Difference Formulas, pg. 368

9. Example 5
Prove the cofunction identity

10. Section 5.4, Sum and Difference Formulas, pg. 368

11. Example 6
Simplify the expression.
a. b.

12. Section 5.4, Sum and Difference Formulas, pg. 368

13. Example 7
Find all solutions of in the interval