### Contents

 PLANE TRIGONOMETRY 1 Signs of the Trigonometric Functions 8 Functions of Complementary Angles 14 CHAPTER II 22 Solution of Right Triangles 28 Proof of Fundamental Formulas 1114 36 THE OBLIQUE TRIANGLE 41 Exercises 50
 CHAPTER VII 78 CHAPTER VIII 93 CHAPTER IX 100 The Six Cases and Examples 106 Geographical Problems 113 CHAPTER XII 119 Relations of Functions 120 APPENDIX 125

### Popular passages

Page 95 - I. The sine of the middle part is equal to the product of the tangents of the adjacent parts.
Page 64 - The logarithm of a quotient is equal to the logarithm of the dividend minus the logarithm of the divisor. , M , ,• , . logi — = log
Page v - To Divide One Number by Another, Subtract the logarithm of the divisor from the logarithm of the dividend, and obtain the antilogarithm of the difference.
Page 17 - The sine of an angle is equal to the sine of its supplement. The sine rule Consider fig.
Page vi - Root of a Number: Divide the logarithm of the number by the index of the root ; the quotient is the logarithm of the required root of the number.
Page 53 - If 2 men start from the same place and travel in opposite directions, one at the rate of 4 miles an hour, and the other at the rate of 5 miles an hour, how far apart will they be at the end of 1 hour ? At the end of 2 hours ? 5 hours?
Page 64 - The logarithm of any power of a number is equal to the logarithm of the number multiplied by the exponent of the power.
Page 64 - The logarithm of the product of two numbers is equal to the sum of the logarithms of the numbers.
Page 46 - Two sides of a triangle, and the angle opposite one of them, being given, to describe the triangle. Let A and B be the given sides, and C the given angle.
Page v - The logarithm of a number is the index of the power to which the base of the system must be raised to equal a given number.