Trigonometry

• -1
• sec θ
• - csc θ
• - sec θ

Please choose the correct sum and difference formula:
sin (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

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)

Find the exact value

• √3

• -√3

• 1/2

• -1/2

cosα cosβ + sinα sinβ =

• sin (α + β)

• sin (α - β)

• cos (α + β)

• cos (α - β)

Tags

CCSS.HSF.TF.C.9

Find the exact value

• √3

• -√3

• 1/2

• -1/2

cos40° cos20° - sin40° sin20° =

• sin (20°)

• 1/2

• cos (20°)

• √3/2

Tags

CCSS.HSF.TF.C.9

Without using a calculator, what is the exact value of
tan20⁰ cot 20⁰?

• 1/2
• 0
• 1
• -1

Which is not a version of the double angle formula for cosines?

• cos²(x)-sin²(x)
• 2cos²x-1
• cos²x+sin²x
• 1-2sin²(x)