1. Sullivan Algebra and Trigonometry: Section 7.2 Objectives of this Section Find the Value of Trigonometric Functions of Acute Angles Use the Fundamental Identities Find the Remaining Trigonometric Functions Given the Value of One Use the Complementary Angle Theorem

2. A triangle in which one angle is a right angle is called a right triangle. The side opposite the right angle is called the hypotenuse, and the remaining two sides are called the legs of the triangle. c b a

3. Initial side Terminal side Acute Angle a b c Right Triangle

4. The six ratios of a right triangle are called trigonometric functions of acute angles and are defined as follows: Function nameAbbreviationValue

6. Find the value of each of the six trigonometric functions of the angle Adjacent 12 13 c = Hypotenuse = 13 b = Opposite = 12

8. Reciprocal Identities Quotient Identities

9. c b a

12. Complementary Angles Theorem Cofunctions of complementary angles are equal.