What is the Pythagorean Identity?
What is the second Pythagorean Identity?
Hint: Divide the first Pythagorean identity by cos²(θ)
What is the double angle formula for sine?
What is the double angle formula for cosine?
Hint: There are three equivalent forms
What is the sum formula for sine: sin(A + B)?
What is the sum formula for cosine: cos(A + B)?
What is the Law of Sines?
What is the Law of Cosines?
Hint: A generalization of the Pythagorean theorem
What is the half-angle formula for sin(θ/2)?
What is the area of a triangle using trigonometry?