Sullivan Algebra and Trigonometry Section 7 4 Objectives

Sullivan Algebra and Trigonometry: Section 7. 4 Objectives of this Section • Find the Exact Value of the Trigonometric Functions for General Angles • Determine the Sign of the Trigonometric Functions of an Angle in a Given Quadrant • Use Coterminal Angles to Find the Exact Value of a Trigonometric Function • Find the Reference Angle of a General Angle • Use the Theorem of Reference Angles

provided no denominator equals 0.

y r (a, b) x

Find the exact value of each of the six trigonometric functions of a positive angle if (-2, 3) is a point on the terminal side. y (-2, 3) x

y x P= (1, 0) P= (a, b)

y P= (0, 1) x

y I (+, +) All positive x

Two angles in standard position are said to be coterminal if they have the same terminal side. y x

Let denote a nonacute angle that lies in a quadrant. The acute angle formed by the terminal side of and either the positive x-axis or the negative x-axis is called the reference angle for Reference Angle

Finding the reference angle 2. Determine the quadrant in which the terminal side of the angle formed by the angle lies.

y x

Reference Angles

Find the exact value of each of the following trigonometric functions using reference angles: