1. Bellringer 3-28 What is the area of a circular sector with radius = 9 cm and a central angle of θ = 45°?

2. Homework Section 5.2 Pg. 251 (17, 21, 24, 28, 29) 17. 20 /3 (20.9 cm) 21. 5 /36 (.44 in) 24. 35.8° 28. 65.45 ft 2 29. 16.97 in 2

3. Section 5.3 – Circular Functions Definition of Sine and Cosine If the terminal side of an angle θ in standard position intersects the unit circle at P(x,y), then cos θ = x and sin θ = y.

4. Sine and Cosine Ex. What is the sin 90°? (Draw circle and find coordinates.)

5. Sine and Cosine (2) What is the cos ?

6. Sine and Cosine (Functions of an Angle) For any angle in standard position with θ, a point P(x,y) on its terminal side, and r =, the sine and cosine functions of θ are as follows: sin θ = cos θ =

7. Example 1 Find the values of sine and cosine functions of an angle in standard position with measure θ if the point with coordinates (3,4) lies on its terminal side.

8. Example 2 Find sin θ when cos θ = and the terminal side of θ is in the first quadrant.

9. 6 Trigonometric Functions Sine, Cosine, Tangent, Cosecant, Secant, Cotangent sin θ = cos θ =tan θ = csc θ = sec θ = cot θ = Notice cosecant is the reciprocal of sine… csc θ = 1/sin θ

10. Example The terminal side of an angle θ in standard position contains the point with coordinates (8, -15). Find the values of all 6 trig. Functions.

11. Chart for signs in Quadrants

12. Homework 5.3 Pg. 260 (25, 28, 32)