Trig Identities

Front

What is the Pythagorean identity for sine and cosine?

Back

sin²θ + cos²θ = 1

Tags

CCSS.HSF.TF.C.8

Front

What is the definition of tangent in terms of sine and cosine?

Back

tan(x) = sin(x)/cos(x)

Tags

CCSS.HSF.TF.A.2

Front

What is the reciprocal identity for sine?

Back

csc(x) = 1/sin(x)

Tags

CCSS.HSF.TF.C.8

Front

What is the reciprocal identity for cosine?

Back

sec(x) = 1/cos(x)

Tags

CCSS.HSF.TF.C.8

Front

What is the reciprocal identity for tangent?

Back

cot(x) = 1/tan(x) = cos(x)/sin(x)

Tags

CCSS.HSF.TF.C.8

Front

What is the identity for secant squared?

Back

sec²θ = 1 + tan²θ

Front

What is the identity for cosecant squared?

Back

csc²θ = 1 + cot²θ

Front

What is the co-function identity for sine and cosine?

Back

sin(90° - θ) = cos(θ) and cos(90° - θ) = sin(θ)

Front

What is the double angle formula for sine?

Back

sin(2θ) = 2sin(θ)cos(θ)

Tags

CCSS.HSF.TF.C.9

Front

What is the double angle formula for cosine?

Back

cos(2θ) = cos²(θ) - sin²(θ)

Tags

CCSS.HSF.TF.C.9