1. 4.1(b) Notes: Radians and Degrees
Date:
4.1(b) Notes: Radians and Degrees
Lesson Objective: Find rectangular coordinates on the unit circle. Describe angles of a circle and use radian and degree measures.
CCSS: F-TF Extend the domain of tri­go­no­me­tric functions using the unit circle.
You will need: a highlighter, calculator

2. Lesson 1: Rectangular Coordinates
Rectangular Coordinates: Use the Pythagorean Theorem

3. Lesson 2: Coterminal Angles
Common Greek Names of Angles: α = alpha, β = beta, γ = gamma, θ = theta

4. Lesson 2: Coterminal Angles
Coterminal Angles: Angles having the same initial and terminal side, but having different radians or degrees.

5. Lesson 2: Coterminal Angles
Coterminal Angles: Angles having the same initial and terminal side, but having different radians or degrees.
Find a coterminal angle.
For the positive angle 9π/4, add 2π.
9π/4
B. For the positive angle 5π/6, subtract 2π.
5π/6
C. For the negative angle –π/3, add 4π.
–π/3

6. Lesson 2: Coterminal Angles

7. Lesson 2: Coterminal Angles

8. Lesson 3: Complementary/Supplementary Angles
Complementary Angles: 2 angles whose sum = 90° or π/2.
Supplementary Angles: 2 angles whose sum = 180° or π.
Find the complement and the supplement to:
π/6
2π/3

9. 4.1(b): Do I Get It? Yes or No
Give the rectangular coordinates for –2π/3
For the positive angle 13π/6, subtract 2π to obtain a coterminal angle.
For the negative angle -2π/3, add 2π to obtain a coterminal angle.
Find the complement and the supplement to 2π/5