Question

Which represents the reference angle for 3pi/4?
A) (3 pi)/4
B) pi/3
C) pi/4
D) pi/6

I have no clue on how to do this. (Looking at my unit circle I think A?)

Answer 1

Reference angles are always measured from the x-axis. So, since 3pi/4 = pi - pi/4, the reference angle is pi/4.

Better go back and review that topic some.

Answer 2

fellows, its c
pi/4

Answer 3

anyone got the full test answers????

Answer 4

This is the Periodic Functions and Trigonometry Unit Test Part 1, but I'm in honors so some may not be the same. If you have a different one, maybe search question # ten. That might have all of your answers.
1) C. 2
2) D. 215°
3) π/4
4) D. -495°
5) A. 0
6) C. 240°
7) A. π
8) C. 131 ft
9) C. 40 centimeters
10) B. y = 4 sin 8θ
11) B. y = sin π/255 θ
12) C. period = 1/4 π, range = -4 ≤ y ≤ 4, amplitude = 4
13) B. y = 4 cos 2θ
14) B. √3
15) B. 1
16) C. The one that looks like a weird upside down arrow or something
17) D. 380 ft
18) √3/2
19) B. 1 + sin θ
20) D. 45°
21) D. 0.64
22) A. 80°
23) C. π/2, 5π/4, 3π/2, 7π/4
24) A. csc θ = 5/4, sec θ = 5/3