2. Trigonometric Functions on Right Triangles

In Exercises 63–68, find the exact value of each expression. Do not use a calculator.cos 12° sin 78° + cos 78° sin 12°

In Exercises 69–70, express the exact value of each function as a single fraction. Do not use a calculator.If f(θ) = 2 cos θ - cos 2θ, find f(𝜋/6).

In Exercises 1–8, a point on the terminal side of angle θ is given. Find the exact value of each of the six trigonometric functions of θ.(-4, 3)

In Exercises 1–8, a point on the terminal side of angle θ is given. Find the exact value of each of the six trigonometric functions of θ.(3, 7)

In Exercises 1–8, a point on the terminal side of angle θ is given. Find the exact value of each of the six trigonometric functions of θ.(5, -5)

In Exercises 1–8, a point on the terminal side of angle θ is given. Find the exact value of each of the six trigonometric functions of θ.(-1, -3)

In Exercises 9–16, evaluate the trigonometric function at the quadrantal angle, or state that the expression is undefined.tan 𝜋

In Exercises 9–16, evaluate the trigonometric function at the quadrantal angle, or state that the expression is undefined.csc 𝜋

In Exercises 9–16, evaluate the trigonometric function at the quadrantal angle, or state that the expression is undefined.cos 3𝜋2

In Exercises 9–16, evaluate the trigonometric function at the quadrantal angle, or state that the expression is undefined.cot 𝜋2

In Exercises 9–16, evaluate the trigonometric function at the quadrantal angle, or state that the expression is undefined.tan 𝜋2

In Exercises 17–22, let θ be an angle in standard position. Name the quadrant in which θ lies.sin θ > 0, cos θ > 0

In Exercises 17–22, let θ be an angle in standard position. Name the quadrant in which θ lies.sin θ < 0, cos θ < 0

In Exercises 17–22, let θ be an angle in standard position. Name the quadrant in which θ lies.tan θ < 0, cos θ < 0

In Exercises 23–34, find the exact value of each of the remaining trigonometric functions of θ.cos θ = -3/5, θ in quadrant III