Ratios of sum and difference of angles Sum and difference of ratios of angles Ratios of the double and half angle. 83-86 91-98 152 152-156 156 157-159 159-162 162-165 166, 167 181, 182 193, 194 200-203 Directed lengths, angles, and areas 294, 295. Algebraical representation of these 296–299. Dependent signs. Signs in Multiplication § 2. Application to Trigonometrical Ratios. Extended definition of ratios Convention as to sign 307-314. Comparison of ratios of related angles 216-220 224, 225 225-229 229-235 235-238 § 1. Sum and Difference of two angles. 326, 327. The addition and subtraction of a right-angle. 246-250 |