7.4

Find the exact value of the expression.
cos(20)cos(40) - sin(20)sin(40)

• 1/4
• 1/2
• √(3)/2
• √(3)

Tags

CCSS.HSF.TF.C.9

Find the exact value of the expression.
sin(5π/12)cos(π/4) - cos(5π/12)sin(π/4)

• 1/2
• -1/2
• -√(2)/2
• √(3)/2

Tags

CCSS.HSF.TF.C.9

Find the exact value. 
cos (265 - 25) = 

• 53/12
• -√(3)/2
• -1/2
• √(3)/2

Tags

CCSS.HSF.TF.C.9

Write the following expression as the sine, cosine, or tangent of an angle.
cos(175)cos(55)+sin(175)sin(55)

• sin(120)
• cos(120)
• cos(230)
• sin(230)

Tags

CCSS.HSF.TF.C.9

Find the exact value of the expression.
cos(20)cos(40) - sin(20)sin(40)

• 1/4
• 1/2
• √(3)/2
• √(3)

Tags

CCSS.HSF.TF.C.9

Use Sum or Difference Identities to find the exact value of
sin(π/12)

• (-√(2)-√(6))/2
• (√(6)-√(2))/4
• (√(2)+√(3))/4
• (-√(6)+√(2))/4

Tags

CCSS.HSF.TF.C.9

Use Sum or Difference Identities to find the exact value of each expression.
cos(75°)

• 1/4
• ( √(6) - √(2) ) / 4
• (√(6) + √(2)) / 4
• (-√(6) - √(2)) / 4

Tags

CCSS.HSF.TF.C.9