1. Warm-up:
HW: pg. 490(1 – 4, 7 – 16, , 45 – 48)

2. 5.4 Sum and Difference Formulas
Objective:
Use the sum and difference formulas

3. Learn these!!

4. Procedure: Finding exact values of trig expressions
Split the given number into the sum/difference of unit circle values we know
Change the problem using the correct formula
Simplify by replacing in trig values

5. Examples: Find the exact values
Split 75o into 30o and 45o since
Use the cosine formula
Replace with Trig values

6. Ex) Evaluating a Trigonometric Function
Find the exact value of sin

7. Examples: Find the exact values

8. Prove:

9. Deriving Reduction Formulas:

10. Deriving Reduction Formulas:

11. Solving a Trigonometric Equation:

12. Sneedlegrit: Find the exact value of
HW: pg. 490(1 – 4, 7 – 16, , 45 – 48)