Pre-Calculus Homework Solutions 230

Pre-Calculus Homework Solutions 230 - 9. Let x represent...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 9. Let x represent the geometric mean. Page 391 Geometry Activity: Trigonometric Identities 1. Sample answer: It is of the form a2 where c 1. 1 2. cos sec ; ta1 n sin 3. cos tan y r x r y x yr rx y x 4. cos sin y , cos r y x x r , tan Multiply by the reciprocal of x . r Multiply. y2 x y2 x2 2 y2 x2 x y2 cot2 x2 y x2 y2 2 y2 x2 y x2 sin x y x y 5. tan2 Original equation x y xr ry x y x2 x x 10. Let 20 x¬ x2¬ x¬ x¬ 11. Let 18 x¬ x2¬ x¬ x¬ 12. Let Original equation cot x r y r 6. c2, cot sin y x y x b2 4 x Multiply by the reciprocal of y . r Multiply. y , cos r 1 sec2 1 r x r2 x2 1 x r , cot x y tan y , sec x 1 (x2) x2 Multiply each side by x2. x2 r2 1 r2 r2 csc2 Simplify. Substitution; y2 x2 Original equation 1 1 r y r2 y2 2 cot x y , sec r2 r y 1 r (y2) y2 x 44 792 792 28.1 x¬ RS. RS QS x 14 52 17 ¬ 25 289 ¬ y2 r2 r2 r2 Simplify. Substitution; x2 x2 Multiply each side by y2. y2 700 700 26.5 x represent the geometric mean. 14. x2 Evaluate exponents. 2 x 35 x2¬ 112 x¬ 112 or 4 7 x¬ 10.6 So RS¬ 10.6. 13. 152 202¬ x2 225 400¬ x2 625¬ x2 625¬ x 25¬ x r x Evaluate exponents. r2 324 324 18 x represent the geometric mean. PS RS ¬ 8 x¬ Original equation 2 x 81 13 2 17 169 289 144 289 144 289 12 17 x2¬ r2 x¬ x¬ 132¬ x2 15. Chapter 7 Study Guide and Review x2 169¬ x2¬ x¬ x¬ 9 92 13 Page 392 Vocabulary and Concept Check 1. 2. 3. 4. 5. 6. 7. true false; opposite; adjacent false; a right true true false; 45°-45°-90° false; depression 16. x y 17. 13 2 13 2 2 2 13 2 2 y 8. Let x represent the geometric mean. 4 x x2 x x 64 64 8 Chapter 7 232 2 x x 13 2 2 18. x y 19. z a a x 16 x x x y Pages 392–396 Lesson-by-Lesson Review 212 441 272 272 or 4 17 16.5 2(6) or 12 63 18 3 2z 2(18 3) or 36 3 ...
View Full Document

This note was uploaded on 12/19/2011 for the course MAC 1140 taught by Professor Dr.zhan during the Fall '10 term at UNF.

Ask a homework question - tutors are online