1. Difference and Sum of Angles
Must do before Lesson 64
L. Marizza A. Bailey

2. Assume we are on the unit circle.
Difference of Angles α θ
Assume we are on the unit circle.

3. Assume we are on the unit circle.
Difference of Angles
α - θ α θ
Assume we are on the unit circle.

4. Assume we are on the unit circle.
Difference of Angles
( cos (α – θ) ,sin (α – θ) )
( cos (α) ,sin (α) )
( cos (θ) ,sin (θ) )
α - θ α θ
Assume we are on the unit circle.

5. Assume we are on the unit circle.
Difference of Angles
( cos (α – θ) ,sin (α – θ) )
( cos (α) ,sin (α) )
( cos (θ) ,sin (θ) )
α - Ө
α - θ
(1,0)
Assume we are on the unit circle.

6. Distances are the same

7. The sum of angles
Write all four sum and difference of angle identities.