What is the period of the function? y=4 cos pi x

A. 1
B. 2
C. pi
D. 2pi

4 answers

The period of any cosine function is 2PI

2PI=PI*x
x=2
y=4cos50
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
Yalll I took one for the team!!
1. What is the periodic of the function- y=4 cos pi x : 2
2. The terminal arm of an angle….: 215 degrees
3.which represents the reference angle for 3pi/4: pi/4
4. Neela’s clock is broken… -465 degrees
5. Evaluate sin 180 degrees: 0
6. If sin theta =1/2 which could NOT be the value of theta: 210 degrees
7. For which value of theta is tan…:2pi
8.a gazebo is located in the center of a large..: 52ft
9. If co 67degrees is close to 2/5 which is closest to the length of NO: 40 cm
10. The graphs - was C for me: y=-4 sin 4 theta
11. A sine function can be used to model light waves: y=sin pi/265 theta
12. Find the period.. y=-4 cos 8x: period =1/4 pi, range = -4<y<4, amplitude =4
13.for particular angle theta…: y=4cos 2theta
14.what is the value of tan(-2pi/3): square root of 3
15. Find the exact value tan 45 degrees: 1
16. Idk how to explain the graph for this but it was A for me
17. A man stand in his balcony…: 380ft
18. What is the value of sin pi/3 : squareroot 3/2
19.simplify the trig expression : 1+cos theta
20. use the unit circle to find.. : 60 degrees
21. Which is the radian measure…: 0.93
22. Which is the degree measure..: 80 degrees
23. What values for theta(o<theta<2pi) satisfy the equation.: pi/2, 4pi/3, 3pi/2,5pi/3
24. For a standard position angle..: csc theta=13/12; sec theta=13/5

I tried my best to make it easy but anything after “:” is the answer.

This is for the periodic functions and trigonometry unit test part 1 (honors algebra 2 b)