Unit Circle: Worksheet 1

Which of the following is true about the unit circle?

a. The center of the circle is at the origin

b. the radius of the circle is 1 unit

• a

• b

• both a and b

• neither a nor b

What are the coordinates of 60° on the unit circle?

• (0, 1)
• (1/2, √3/2)
• (√3/2, 1/2)
• (√2/2, 1/2)

sinθ is positive in

• the 1st and 2nd quadrants
• the 1st and 3rd quadrants
• the 1st and 4th quadrants
• the 2nd and 3rd quadrants

cosθ is positive in

• the 1st and 2nd quadrants
• the 1st and 3rd quadrants
• the 1st and 4th quadrants
• the 2nd and 3rd quadrants

What is sin 45°?

• 1
• ^√3/₂
• ½
• ^√2/₂

What is sin 45°?

• 1
• ^√3/₂
• ½
• ^√2/₂

What is cos 30°?

• ^√3/₂
• ½
• ^√2/₂
• 1

What is the exact coordinates of  3π/4 on the unit circle?

• (−√2∕2, √2∕2)
• (−√2∕2, −√2∕2)
• (−√3∕2, −√2∕2)
• (√2∕2, −√2∕2)

What is cos 90°?

• ½
• undefined
• 1
• 0

sin π/4

• √2∕2
• 1/2
• √3/2
• 0