Trigonometric Identities

Front

What is the Pythagorean identity?

Back

sin²(θ) + cos²(θ) = 1

Front

What is the sine of an angle in terms of the opposite side and hypotenuse?

Back

sin(θ) = opposite/hypotenuse

Front

What is the cosine of an angle in terms of the adjacent side and hypotenuse?

Back

cos(θ) = adjacent/hypotenuse

Front

What is the tangent of an angle in terms of sine and cosine?

Back

tan(θ) = sin(θ)/cos(θ)

Front

What is the reciprocal identity for sine?

Back

csc(θ) = 1/sin(θ)

Front

What is the reciprocal identity for cosine?

Back

sec(θ) = 1/cos(θ)

Front

What is the reciprocal identity for tangent?

Back

cot(θ) = 1/tan(θ)

Front

What is the co-function identity for sine?

Back

sin(θ) = cos(90° - θ)

Front

What is the co-function identity for cosine?

Back

cos(θ) = sin(90° - θ)

Front

What is the co-function identity for tangent?

Back

tan(θ) = cot(90° - θ)