1. Warm up

2. - Angle Measure and the Unit Circle (First Quadrant) Chapter 4 Understanding Trigonometric Functions Language Objectives: We will we will exploring angle measure and the unit circle by As a class complete the Activity 11B

3. Angle-An angle is formed by two rays that share the same fixed endpoint, called the vertex. Initial side-The initial side of an angle is the ray that remains fixed. Terminal side-The terminal side of an angle is the ray that rotates. Positive angle-A positive angle is a rotation of the terminal side in the counterclockwise direction. Negative angle-A negative angle is a rotation of the terminal side in the clockwise direction. Standard position-An angle in standard position has its vertex at the origin and the initial side on the positive x-axis. Vocabulary

5. The Unit Circle Let α be an angle in standard position with terminal side that intersects the unit circle at P(x, y). The radian measure of α is the length of the corresponding arc on the unit circle.

7. Exit directions Do: As a class complete the Activity 11B. Put: In box No. 3 Finish By: 10.50 When done do: Complete Worksheet 11A