Use the identities for the cosine of a sum or difference to write each expression as a trigonometric function of θ alone.
cos(90° - θ)

Find one value of θ or x that satisfies each of the following.

sec x = csc (2π/3)

Find one value of θ or x that satisfies each of the following.

cos x = sin (π/12)

Write each function as an expression involving functions of θ or x alone. See Example 2.

tan (π/4 + x)

Write each function as an expression involving functions of θ or x alone. See Example 2.

sin (3π/4 - x)

Write each function as an expression involving functions of θ or x alone. See Example 2.

tan(180° + θ)

Use the identities for the cosine of a sum or difference to write each expression as a trigonometric function of θ alone.

cos(θ - 270°)

Write each function as an expression involving functions of θ or x alone. See Example 2.

sin(π + x)

Express each function as a trigonometric function of x. See Example 5.

cos 3x