Unit Circle (sine/cosine - degrees only)

We use the Unit Circle to construct the sine and the cosine functions. The unit circle is called the unit circle because:

• It is only one circle

• The area of the circle is equal to one

• Because its radius is equal to one

• Because its circumference is equal to one

Tags

CCSS.HSF.TF.C.8

sin 210°

• 
  

  $-\frac{1}{2}$

• $-\ \frac{\sqrt{3}}{2}$
  

• $\frac{1}{2}$

• $\frac{\sqrt{3}}{2}$
  

Tags

CCSS.HSF.TF.A.2

CCSS.HSF.TF.A.3

CCSS.HSF.TF.C.8

cos 90°

• 0

• 1

• -1

• undefined

Tags

CCSS.HSF.TF.A.2

CCSS.HSF.TF.A.3

CCSS.HSF.TF.C.8

cos 135°

• √2/2

• -√2/2

• √3/2

• -√3/2

Tags

CCSS.HSF.TF.A.3

CCSS.HSF.TF.C.8

sin 180°

• 0

• 1

• -1

• undefined

Tags

CCSS.HSF.TF.A.3

cos 180°

• 0

• 1

• -1

• undefined

Tags

CCSS.HSF.TF.A.2

CCSS.HSF.TF.A.3

sin 150°

• 1/2

• -1/2

• √3/2

• -√3/2

Tags

CCSS.HSF.TF.A.3

cos(60°)

• 0
• 1/2
• √3/2
• 1

Tags

CCSS.HSF.TF.A.3

CCSS.HSG.SRT.C.6

cos 300^o

• -1/2

• 1/2

• √3/2

• -√3/2

Tags

CCSS.HSF.TF.A.2

CCSS.HSF.TF.A.3

CCSS.HSF.TF.A.4

CCSS.HSF.TF.C.8

What is the radius of a unit circle?

• 1
• 2
• 1/2
• 0

Tags

CCSS.HSF.TF.A.2