Introduction to periodic functions. Measuring angles with radians. Converting degrees and radians.

1. Why are there 360° in a circle?
What is the most quot;naturalquot; way to measure
angles?
Periodic Functions
Circles by flickr user tydan

4. How do we convert between radians and degrees?
D is an angle in degrees
R is an angle in radians
θ is called quot;thetaquot;
Examples:
Find 30° in radians ... Find 20° in radians ...

5. Find 250° in radians ... Find in degrees ...

6. Find -18° in radians ... Find in degrees ...

7. Find in degrees ...
COTERMINAL ANGLES

8. What does periodic mean?
Clock photo source

9. Convert the following to radian. Write your answers using π and in
decimal form to two decimal places. HOMEWORK
105° -11° 450°

10. Convert the following to degrees. Write your answers rounded to
the nearest degree. HOMEWORK
7π 3.52 -2
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