1. Right Triangles and Trigonometry
Chapter 9
Right Triangles and Trigonometry

2. Section 5 Trigonometric Ratios

3. GOAL 1: Finding Trigonometric Ratios

5. Example 1: Finding Trigonometric Ratios Compare the sine, the cosine, and the tangent ratios for <A in each triangle below. sin = sin = cos = cos = tan = tan =

6. Example 2: Finding Trigonometric Ratios
Find the sine, the cosine, and the tangent of the indicated angle.
<S
sin =
cos =
tan =
b) <R

7. Notes: Trigonometric ratios are frequently expressed as decimal approximations. You can find trigonometric ratios for 30*, 45*, and 60* by applying what you know about special right triangles.

8. Example 3: Trigonometric Ratios for 45
Example 3: Trigonometric Ratios for 45* Find the sine, the cosine, and the tangent of 45*.

9. Example 4: Trigonometric Ratios for 30
Example 4: Trigonometric Ratios for 30* Find the sine, the cosine, and the tangent of 30*.

10. Example 5: Using a Calculator

13. GOAL 2: Using Trigonometric Ratios in Real Life

14. Example 6: Indirect Measurement

15. Example 7: Estimating a Distance

16. EXIT SLIP