4/28/2016
13.2 – Coterminal Angles
Objective: TSW draw angles is
standard position and calculate
coterminal angles.
Angle in Standard Position
The Unit Circle – Introduction
1. Circle with radius of 1
1 Revolution = 360°
2 Revolutions = 720°
2. Positive angles move
counterclockwise around
the circle
3. Negative angles move
clockwise around the circle
Quadrantal Angles (positive)
Quadrantal Angles (negative)
Angles in standard position whose terminal side
is on the x or y axis.
Angles in standard position whose terminal side
is on the x or y axis.
1
4/28/2016
Draw an angle with the given measure
in standard position:
1. 70°
2. -130°
Coterminal Angles
co – terminal
3. 430°
with, joint,
or together
ending
Coterminal Angles – angles that end at the
same spot
What do coterminal angles look like?
http://www.mathopenref.com/coterminal.html
Your Turn, find two positive and two negative
coterminal angles.
8. 45°
9. 250°
Find a coterminal angle for each of the
following angles.
4. 70°
6. –20°
5. 250°
7. –220°
Solving for coterminal angles of least
measure
10. –20°
If the angle is
If the angle is
positive, subtract negative, add 360°
360°from the given to the given angle.
angle.
You know you are done when your angle
measure is positive, and less than 360°
2
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Find the angles of least positive
measure coterminal with each angle.
11. 1106°
12. -150°
Your Turn…
13. –603°
14. 1500°
Homework
Worksheet
3