4.1-4.3 trigonometry

counterclockwise rotation

positive angle

clockwise rotation

negative angle

coterminal angles

two angles that have the same initial and terminal angles

how to find the coterminal angle?

add or subtract by 2pi

one full revolution

2pi or 360 degrees

half of a revolution

pi or 180 degrees

fourth of a revolution

pi/2 radians

quadrant 1

between 0 and 90 degrees

between 0 and ½ pi

1.57

quadrant 2

between 90 and 180 degrees

between 1/2pi and pi

3.14

quadrant 3

between 180 and 270

between pi and ¾ pi

4.71

quadrant 4

between 270 and 360

between ¾ pi and 2pi

6.28

how to find complementary

subtract from pi/2

how to find supplementary

subtract from pi

θ =

s/r

how to convert degrees to radians

multiply by pi rad/180

what formula can be used to measure arc length?

s= theta x r

area of a sector formula (central angle must be in radians)

½ r² theta

how to find the csc of cos 28

1/cos 28