1. Verifying Trigonometric Identities (Section 5-2)

2. Guidelines for Verifying Trigonometric Identities
Work with one side of the equation at a time. It is often better to work with the more complicated side first.
Look for opportunities to factor an expression, add fractions, square a binomial, or create a monomial denominator.
Look for opportunities to use the fundamental identities. Note which functions are in the final expression you want. Sines and cosines pair up well, as do secants and tangents, and cosecants and cotangents.
If the preceding guidelines do no help, try converting all terms to sines and cosines.
Always try something. Even making an attempt that leads to a dead end proves insight.

3. Verify the identity.
Example 1

4. Verify the identity.
Example 2

5. Verify the identity.
Example 3

6. Verify the identity.
Example 4

7. Verify the identity.
Example 5

8. Verify the identity.
Example 6

9. Verify the identity.
Example 7

10. Verify the identity.
Example 8

11. Verify the identity.
Example 8

12. Verify the identity.
Example 9

13. Verify the identity.
Example 10

14. Verify the identity.
Example 11

15. Verify the identity.
Example 12

16. Verify the identity.
Example 13

17. Verify the identity.
Example 14

18. Verify the identity.
Example 15

19. Verify the identity.
Example 16

20. Verify the identity.
Example 17

21. Verify the identity.
Example 18

22. Powers of trigonometric functions are rewritten to be useful in calculus. Verify the identity.
Example 19

23. Powers of trigonometric functions are rewritten to be useful in calculus. Verify the identity.
Example 20

24. Powers of trigonometric functions are rewritten to be useful in calculus. Verify the identity.
Example 21

25. HW #41 pg 365-366 (1-10 all, 19, 20, 21-29odd, 31-49 odd, 55, 57)

26. Use the cofunction identities to evaluate the expression without using a calculator.
Example 22

27. Use the cofunction identities to evaluate the expression without using a calculator.
Example 23

28. a) Verify the identity. b) determine if the identity is true for the given value of x.
Example 24

29. HW #42 pg (59, 61, 63-69all, 71, 72, 77-83odd)