Lesson Plan

Define sine and cosine as the y- and x-coordinates of a point on the unit circle corresponding to a given angle

Evaluate sine and cosine for angles in all four quadrants using the unit circle

Determine the signs of sine and cosine in each quadrant and explain why using coordinates

Extend the definitions to negative angles (clockwise rotation) and angles greater than 2pi

Find reference angles and use them to evaluate trigonometric functions for non-first-quadrant angles

Explain how the unit circle allows trigonometric functions to accept any real number as input

HSF.TF.A.2

HSF.TF.A.2: Explain how the unit circle in the coordinate plane enables the extension of trigonometric functions to all real numbers, interpreted as radian measures of angles traversed counterclockwise around the unit circle.