Plane trigonometry, by S.L. Loney.

CONTENTS.
PART I.
CHAP. PAGE
I. Measurement of angles. Sexagesimal and Centesimal
Measure...... 1
Circular, or Radian, Measure.... 5
II. Trigonometrical Ratios for angles less than a right
angle..... 19
Values for angles of 45~, 30~, 60~, 90~ and 0~.. 32
III. Simple problems in Heights and Distances.. 40
IV. Applications of algebraic signs to Trigonometry. 47
Tracing the changes in the ratios. 52
V. Trigonometrical ratios of angles of any size. Ratios
for - 0, 90~ - O, 90~ +...... 64
VI. General expressions for all angles having a given
trigonometrical ratio..... 76
VII. Ratios of the sum and difference of two angles. 87
Product Formulae...... 93
VIII. Ratios of multiple and submultiple angles.. 105
Explanation of ambiguities.... 117
Angles of 18~, 36~, and 9~.. 126
IX. Identities and trigonometrical equations... 131
X. Logarithms....... 146
Tables of logarithms...... 152