Problem of the Day
What quadrant does the terminal side of the angle lie
in?
1. ­175
2. 800
3. ­600
6­1 Angles and Their Measures
Angles in the Coordinate Plane
Initial Side
Terminal Side
More About Angles in the Coordinate Plane
Quadrants
6­1 Angles and Their Measures
What quadrant does the terminal side of 250o lie in?
6­1 Angles and Their Measures
What quadrant does the terminal side of ­195o lie in?
6­1 Angles and Their Measures
What quadrant does the terminal side of 580o lie in?
Radian Measure
= s/r
central angle of a circle
(in radians)
s = arc length
r = length of the radius of circle
What is 1 radian?
Find the radian measure of a central angle opposite an arc of 36 feet in a circle with radius 12 feet.
Find the radian measure of a central angle opposite an arc of 120 inches in a circle with radius 22 inches.
Find the radian measure of a central angle for the entire circumference of a circle with radius 1 m.
Computing radian measure
Table 1(pg 418)
Radians
Degrees 30 45
180
360
Find 2 coterminal(1 positive and 1 negative) angles
130
Readings and examples: pages 414­421
Homework: pgs 421­422: 1­8, 17­19, 22, 23, 48­61, 67­76