2. Lesson Quiz Lesson Quiz Lesson Presentation Lesson Presentation Lesson 9.2 Define General Angles and Use Radian Measure Warm-Up Standard Accessed: Students will prove, apply, and model trigonometric functions and ratios.

3. Warm-Up Write the expression in simplest form. 5. A compact disk has radius 6 centimeters. Find its circumference and area to the nearest tenth.

4. Vocabulary Angle with its vertex at the origin and its initial side on the positive x -axis. Terminal side is the end of your angle rotation. It is the measure of an angle in standard position whose terminal side intercepts an arc of length r.

5. Vocabulary Degrees: Radians: Degrees: Radians:

6. Essential Understandings What is positive and negative measure?  Angles with positive measure result from counterclockwise rotation. Angles with negative measure result from clockwise rotation.

7. Draw angles in standard position EXAMPLE 1 Draw an angle with the given measure in standard position.

8. Find coterminal angles EXAMPLE 2 SOLUTION Find one positive angle and one negative angle that are coterminal with the angle.

9. Convert between degrees and radians EXAMPLE 3 SOLUTION Convert the given angle measure.

10. Vocabulary

11. Solve a real – world problem EXAMPLE 4 Camp KIS Children at KIS day camp are playing a game on a circular area. The shaded sector in the figure is called the “safe zone”, and is marked off by rope along its outer edge. Find the length of the rope and the area of the safe zone in radians.

12. Lesson 9.2 Homework: Practice B Practice C “Honors”