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CHAPTER
8 Right Triangle Trigonometry
Chapter Outline
8.1 Pythagorean Theorem and Pythagorean Triples
8.2 APPLICATIONS OF THEPYTHAGOREANTHEOREM
8.3 INSCRIBEDSIMILARTRIANGLES
8.4 45-45-90 RIGHTTRIANGLES
8.5 30-60-90 RIGHTTRIANGLES
8.6 SINE, COSINE, TANGENT
8.7 TRIGONOMETRICRATIOS WITH ACALCULATOR
8.8 TRIGONOMETRYWORDPROBLEMS
8.9 INVERSETRIGONOMETRICRATIOS
8.10 LAWS OFSINES ANDCOSINES
Introduction
Chapter 8 explores right triangles in far more depth than Chapters 4 and 5. Recall that a right triangle is a triangle
with exactly one right angle. In this chapter, we will first prove the Pythagorean Theorem and its converse, followed
by analyzing the sides of certain types of triangles. Then, we will introduce trigonometry, which starts with the
tangent, sine and cosine ratios. Finally, we will extend sine and cosine to any triangle, through the Law of Sines and
the Law of Cosines.