1. Section 4.3 The Unit Circle

2. (0, 1) (0, -1) (1, 0)(-1, 0) 0, 0˚ 2π, 360˚ π2π2, 90˚ π, 180˚ 3π 2, 270˚ Quadrantal Angles “All Students Take Calculus” tells you where each trig function is positive. A S TC

3. Let’s begin with an easy family… What are the coordinates? Now, reflect the triangle to the second quadrant…

4. What are the coordinates? Now, reflect the triangle to the third quadrant…

5. What are the coordinates? Now, reflect the triangle to the fourth quadrant…

6. What are the coordinates?

7. EX. Evaluate the six trig functions at θ =. **REMEMBER!!! cos θ is represented by the x-coordinates and sin θ is represented by the y-coordinates.**

8. EX. Evaluate the six trig functions at θ =. Homework: worksheet

9. Now, reflect the triangle to the second quadrant. Complete the family…

10. Now, reflect the triangle to the third quadrant.

11. Now, reflect the triangle to the fourth quadrant. What are the coordinates?

13. EX. Evaluate the six trig functions at θ =.

14. Homework: worksheet

15. Complete the family… Now, reflect the triangle to the second quadrant. 60˚

16. What are the coordinates? Now, reflect the triangle to the third quadrant.

17. What are the coordinates? Now, reflect the triangle to the fourth quadrant.

18. What are the coordinates?

19. Shortcut to remember ordered pairs in quadrant 1 1322311322312 1)Parenthesis 2)Fractions with denominator of 2 3) 4) Square roots

20. EX. Evaluate the six trig functions at θ =.

21. Homework: worksheet