Radians Formalized

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SWBAT define the meaning of radian angle measures.

Big Idea

This lesson formally defines radian measurement and gives students the opportunity to practice converting between degree and radian angle measurements .

Vocabulary and Warm-up

5 minutes

Explanation and Practice: Radians Formalized

45 minutes

Using today’s flipchart, Flipchart_Radians,  I will model for students how to apply the definition of radians and find unknown arc length or radius lengths. Students will also review/formalize in their notes how to convert between radian and degree angle measurements.

Using page 5 of today’s flipchart, I will model how to apply the formula to find the missing angle measurement and arc length using the two example problems.  Students will be encouraged to take notes on this section.

On page 7 of the flipchart, I would like for my students to answer these questions using a think-pair-share. I would like for my students to have an opportunity to think about these questions independently and then have a chance to talk it over in their teams before sharing with the class. I think it is important for students to have time to develop their own understanding about how we can divide up the sections of a complete rotation to determine the radian measurement. This skill will help student greatly in the next two lessons as we begin to build the unit circle.

On pages 8-10, I plan to model the first two problems (a and b) for students. And then have them independently solve the third problem (part c) before we review that answers.   


Assign Homework 2 - Trigonometric Functions.docx for homework this evening.