Period, Amplitude and Unit Circle

Identify the angle of rotation

Using the unit circle. In which quadrant on the unit circle is sine positive? 

• I and II

• II and III

• III and IV

• I and III

If no dilations exist, what is the normal period of a sine or cosine function?

• 1/2π

• 2π

• π

• π/2

What is the period of y = 4Cos(2x)?

• 4π

• π

• 2π

• π/2

What is the period of y=4cos(5x)

• 2π/5

• 5π/2

• 5

• 5π

Consider the graph of 
y = 4cos(θ/3) - 1. What is the amplitude and period of this graph? 

• Amplitude is 3, period is 1440^o

• Amplitude is 3, period is 120^o

• Amplitude is 4, period is 120^o

• Amplitude is 4, period is 1080^o

What is the period of this cosine graph?