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Chapter 14 Trigonometric Functions
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall 14.2 Right Triangle Trigonometry
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall
Trigonometry values for a given angle are always the same no matter how large the triangle is
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall Example Find the value of each of the six trigonometric functions of in the figure shown. Solution Use the Pythagorean Theorem to find c.
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall
Example Given find the value of each of the four remaining trigonometric functions. Solution Determine tangent by using the quotient identity. continued
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall Given find the value of each of the four remaining trigonometric functions.
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall
Example Given that is an acute angle, find the value of cos using a trigonometric identity. Solution Use the Pythagorean identity.
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Example Find a cofunction with the same value as the given expression: sin 62 . Solution Find the complement of the angle.
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Example Sighting the top of the building, a surveyor measured the angle of elevation to be 22 . The transit is 5 feet above the ground and 300 feet from the building. Find the building’s height. Solution continued
Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall Sighting the top of the building, a surveyor measured the angle of elevation to be 22 . The transit is 5 feet above the ground and 300 feet from the building. Find the building’s height. The height of the part of the building above the transit is approximately 121 feet. Thus, the height of the building is determined by adding the transit’s height feet = 126 feet