Download MRN11 Lesson 5 - Forest Hills High School

MRN11
Spring-Lesson 5
Aim: How do we find and use reference angles?
Do Now:
1) Determine the signs for the following functions:
a) sin 35
b) sin 300
c) sin 240
d) cos 220
e) cos(-345)
f) cos(-195)
g) tan -920
h) tan 700
2) What quadrant is  in if cos> 0 and tan< 0 ?
3) What quadrant is  in if cos> 0 and tan0 ?
4) What quadrant is  in if sin> 0 and cos< 0 ?
5) Find the exact value of the following trig functions:
a) sin 30°
b) sin 45°
How do we find the value of sin1350?
c) sin 60°
d) sin 135°
Step 1: ______________________________
Step 2: _____________________________
___________________________________
Step 3: _____________________________
___________________________________
Step 4: _____________________________
___________________________________
_______________________- the acute angle between the terminal side and the x-axis
6) Find the value of:
a) cos135o
For all reference angles in Quadrant 2:
____________________________
b)
tan135o
7) Find the value of:
a) sin210o
For all reference angles in Quadrant 3:
____________________________
b)
cos210o
c) tan210o
8) Find the value of:
For all reference angles in Quadrant 4:
a) sin300o
____________________________
b)
cos300o
c) tan300o
9) a) What is the reference angle of θ = 500?
For all reference angles in Quadrant 1:
____________________________
b) What is θr for any angle in QI ?
Reference Angles
10) For each angle with the given degree measure, find the measure of the reference
angle.
a) 110o
b) 282o
c) -134o
d) 40o
11) Express each given function in terms of a function value of a positive acute
angle(Reference angle)
a) sin 290o
b) cos 195o
c) tan 135o
12) Find the exact values of the following trig functions
a) cos 315o
b) cos -60o
c) sin 420o
13) Which of the following is equivalent to cos2100
(a) sin300
(b) sin2100
(c) -cos300
(d) -cos600
PRACTICE
14) Express each given function in terms of a function value of a positive acute
angle(Reference angle)
a) sin -330o
b) cos 120o
c) cos 225o
15) Find the exact values of the following trig functions
a) tan 315o
b) tan 210o
c)tan -120o