MAT & Trig
Notes 2.2 – Day 2
Mathematician:
PART I - Reference Angles Reminder
Helpful
Hints
 Add or Subtract 360o to find an angle on the circle (between 0o and 360o).
 Draw your triangle to identify where the reference angle is.
 Figure out how much over/under 180o you are if you land in QII or QIII.
 Figure out how much you have left to make 360o if you land in QIV.
Find the reference angle for each of the following.
EX 1:
510o
EX 2:
-300o
EX 3:
225o
EX 4:
1050o
This is an alternative to thinking through the process in your head – but you need to memorize!
Original Angle = A and Reference Angle = 
QII
  180  A
QIII
  A  180
QI
QIV
 A
  360  A
PART II - Finding Exact Values (Using reference angles….)
Helpful
Hints
 Identify the reference angle – remember it must be between 0o and 90o.
 Use the reference angle values on your “chart”.
 Use the correct signs by identifying the correct quadrant that the angle lies in.
Find the exact values of the following trig functions for each angle.
EX 5: sin (240o) = _____
Reference Angle =
Quadrant = _____
Reference Angle =
Quadrant = _____
Reference Angle =
Quadrant = _____
cos (240o) = _____
tan (240o) = _____
EX 6: sin (-210o) = _____
cos (-210o) = _____
tan (-210o) = _____
EX 7: sin (675o) = _____
cos (675o) = _____
tan (675o) = _____