This investigation extends a 25-point geometric system for defining a 25-point trigonometry whose properties are analogous to those of the trigonometry of the Euclidean plane. These properties include definitions of trigonometric functions arising from ratios of sides of right triangles, the relations of elements of a given triangle through the…

An examination problem and solution gives rise to the question of whether there actually exists a theorem concerning the minimal period of the sum of certain periodic functions. The author discusses such a theorem and uses the situation to support mathematical education as opposed to the teaching of mathematics. (MN)

A model, easily constructed by students, is used to assist in seeking basic Pythagorean identities used to prove more complex ones. (MNS)

Functions defined on a unit square are considered, so that a basis may be established to carry over important features to the circular functions. (DT)

This textbook discusses ratios and proportions; the circle and measurement of angles; proportions of figures--measurement of areas; regular polygons--measurement of the circle; planes and polyhedral angles; polyhedrons; the cylinder, cone, and sphere; spherical geometry; plane trigonometry; analytical trigonometry; spherical trigonometry; and…

This textbook presents principles, ratios and proportions, the circle and measurement of angles, regular polygons and measurement of the circle, planes and solid angles, polyhedrons, the three round bodies, analytical trigonometry, plane and spherical trigonometry, and mensuration. [This book was revised and adapted by Charles Davies.]

This textbook presents principles, ratios and proportions, the circle and measurement of angles, regular polygons and measurement of the circle, planes and solid angles, polyhedrons, the three round bodies, analytical trigonometry, plane and spherical trigonometry, and mensuration. [This book was revised and adapted by Charles Davies.]

This textbook presents principles, ratios and proportions, the circle and measurement of angles, regular polygons and measurement of the circle, planes and solid angles, polyhedrons, the three round bodies, analytical trigonometry, plane and spherical trigonometry, and mensuration. [This book was revised and adapted by Charles Davies.]

This textbook presents principles, ratios and proportions, the circle and measurement of angles, regular polygons and measurement of the circle, planes and solid angles, polyhedrons, the three round bodies, analytical trigonometry, plane and spherical trigonometry, and mensuration. [This book was revised and adapted by Charles Davies.]

This textbook presents principles, ratios and proportions, the circle and measurement of angles, regular polygons and measurement of the circle, planes and solid angles, polyhedrons, the three round bodies, analytical trigonometry, plane and spherical trigonometry, and mensuration. [This book was adapted by Charles Davies.]

Develops formulas for the number of bounces of a ball on a billiard table given an original path-angle. (MM)