What is the Pythagorean identity for sine and cosine?
sin²(θ) + cos²(θ) = 1.
How do you simplify sin(-θ)?
sin(-θ) = -sin(θ).
What is the value of tan(θ) in terms of sine and cosine?
tan(θ) = sin(θ) / cos(θ).
What is the reciprocal identity for cosecant?
csc(θ) = 1/sin(θ).
What is the identity for secant in terms of cosine?
sec(θ) = 1/cos(θ).
How do you simplify cos(θ + π)?
cos(θ + π) = -cos(θ).
What is the angle sum identity for sine?
sin(α + β) = sin(α)cos(β) + cos(α)sin(β).
How do you express cotangent in terms of sine and cosine?
cot(θ) = cos(θ) / sin(θ).
What is the double angle formula for sine?
sin(2θ) = 2sin(θ)cos(θ).
How do you simplify cos(-θ)?
cos(-θ) = cos(θ).