What is the basic sine identity?
sin²(θ) + cos²(θ) = 1
What is the basic cosine identity?
cos²(θ) = 1 - sin²(θ)
What is the basic tangent identity?
tan(θ) = sin(θ) / cos(θ)
True or False: sin(θ) is equal to cos(90° - θ).
True
Fill in the blank: The identity tan(θ) can also be expressed as _____ in terms of sine and cosine.
sin(θ) / cos(θ)
What is the Pythagorean identity?
sin²(θ) + cos²(θ) = 1
What is the identity for secant?
sec(θ) = 1 / cos(θ)
What is the identity for cosecant?
csc(θ) = 1 / sin(θ)
What is the identity for cotangent?
cot(θ) = 1 / tan(θ)
What is the double angle identity for sine?
sin(2θ) = 2sin(θ)cos(θ)
What is the double angle identity for cosine?
cos(2θ) = cos²(θ) - sin²(θ)
What is the identity for sin(-θ)?
sin(-θ) = -sin(θ)
What is the identity for cos(-θ)?
cos(-θ) = cos(θ)
True or False: The identity sin(θ + φ) = sin(θ)cos(φ) + cos(θ)sin(φ) is called the sine addition formula.
True
What is the sine subtraction formula?
sin(θ - φ) = sin(θ)cos(φ) - cos(θ)sin(φ)
What is the cosine addition formula?
cos(θ + φ) = cos(θ)cos(φ) - sin(θ)sin(φ)
What is the cosine subtraction formula?
cos(θ - φ) = cos(θ)cos(φ) + sin(θ)sin(φ)
Fill in the blank: The identity tan(θ + φ) can be expressed as _____ in terms of sine and cosine.
(tan(θ) + tan(φ)) / (1 - tan(θ)tan(φ))
What is the relationship between cotangent and tangent?
cot(θ) = 1/tan(θ)
What is the identity for sin²(θ) in terms of cos²(θ)?
sin²(θ) = 1 - cos²(θ)
What is the identity for cos²(θ) in terms of sin²(θ)?
cos²(θ) = 1 - sin²(θ)
True or False: The sum of angles identity for tangent is tan(θ + φ) = tan(θ) + tan(φ).
False
What is the cofunction identity for sine?
sin(θ) = cos(90° - θ)
What is the cofunction identity for cosine?
cos(θ) = sin(90° - θ)
