Identities - Sum and Difference, Double Angle and Half Angles

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.
cos (5π/18 - π/9)

• √(3)/2
• 1/4
• 1/2
• 1

Tags

CCSS.HSF.TF.C.9

Please choose the correct sum and difference formula:
cos (α-β) =

• sin α cos β + cos α sin β
• sin α cos β - cos α sin β
• cos α cos β - sin α sin β
• cos α cos β + sin α sin β

Tags

CCSS.HSF.TF.C.9

Simplify
sin(x+π)

• -1
• csc(x)
• sin(x)
• -sin(x)

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

Please find the sum and difference: cos(60°)cos(45°) - sin(60°)sin(45°)

• 0
• 1
• (√2-√6)/4
• (√8)/4

Tags

CCSS.HSF.TF.C.9

expand
cos(2θ)

• cos²θ-sin²θ
• 2sinθcos
• 2cos²+1
• sin²θ-1

Tags

CCSS.HSF.TF.C.9

Which of the following is NOT
a solution to
sin θ = √(3) / 2 ?

• π / 3
• 2π / 3
• 5π / 3
• 7π / 3

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)

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

• 1/4
• 1/2
• √(3)/2
• √(3)