1. Trig. Functions & the Unit Circle

2. Trigonometry & the Unit Circle VERY important Trig. Identity

3. What is the Unit Circle? A circle with radius 1, centered at the origin (0,0) Used to find the trigonometric ratios of each of any angle that is a multiple of 30 or 45.

4. Filling out unit circle Activity! Create a 45-45-90 triangle with hypotenuse 1 Create a 30-60-90 triangle with hypotenuse 1 Label the lengths of each side Use these triangles to find the x-y coordinate of each angle’s point of intersection with the unit circle.

5. The 45-45-90 Triangle 1

6. The 30-60-90 Triangle 1 30 60

9. Example 1– Evaluate the Trig. Functions NO CALCULATOR 0 DNE 0

10. Example 2 – Find Trig. Functions Using a Point on the Unit Circle

11. Homework Worksheet! Workbook p. 73: 21-26