Trig Angle Formulas

Front

What is the double angle formula for cosine?

Back

The double angle formula for cosine is given by: @@ \cos(2u) = \cos^2(u) - \sin^2(u) = 2\cos^2(u) - 1 = 1 - 2\sin^2(u)@@.

Front

What is the double angle formula for sine?

Back

The double angle formula for sine is given by: @@ \sin(2u) = 2\sin(u)\cos(u)@@.

Front

How can you express cos(20)cos(40) - sin(20)sin(40) using a double angle formula?

Back

Front

What is the value of sin(π/12) using sum or difference identities?

Back

Front

What is the relationship between sin^2(u) and sin(2u)?

Back

Front

What is the value of sin(2u) in terms of sin(u) and cos(u)?

Back

Front

How do you express cos(175)cos(55) + sin(175)sin(55) using a double angle formula?

Back

Front

What is the value of sin(2u) when u = 30°?

Back

Front

What is the double angle formula for tangent?

Back

Front

How can you derive the double angle formula for cosine from the Pythagorean identity?

Back