Solve Using the Unit Circle

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

• A. I and II

• B. II and III

• C. I and IV

• D. I and III

Based on the unit circle, what is the value of cos?

• y

• x

• x/y

• y/x

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

Solve
cos²θ = ½ 
on θ∈[0, 2π)

• θ = π /4, 7π /4

• θ = π /4, 3π /4

• θ = 3π /4, 5π /4

• θ = π /4, 3π /4, 5π /4, 7π /4

• 1
• -1
• 0
• √2/2

If cos x = 1/2, find all possible values of x where 0

• 60^o and 300^o

• 30^o and 150^o

• 30^o and 330^o

• 60^o and 120^o