This publication, with alterations and amendments, has been adapted to the use of American surveyors. The first section discusses decimal fractions, the square root, geometrical definitions, theorems and problems, and logarithm numbers, signs, and tangents. The second section contains plane trigonometry right angled and oblique, with its…

Brief articles on topological regular solids giving a proof of Euler's Theorem and the Regularity Theorem; calculus theorems; including a limit theorem, the Law of the Man, and the Intermediate Value Theorem, applied to catching calves, drunk cowboys, and the border of Montana Respectively; and a discussion of the inequality tan A<A<sin A…

A mathematical misteak" is an incorrect operation that leads to a correct result. An introduction to the use of the misteak" to emphasize the mathematical operations being taught. Examples and brief explanations of several types of misteaks" are given. (FL)

The notion that the area of an inscribed n-sided polygon approaches the area of a circle as n approaches infinity leads to some interesting limits involving trigonometric functions. (MP)

An identity for sin x/x is proved. Rate of convergence, a geometric interpretation, and an application from physics are discussed. (DT)

Introduces two methods of introducing trigonometry: ratio method and unit circle method. Presents a teaching experiment with two groups of students, half of whom were taught with ratio method and the other half with unit circle method. Concludes that ratio method students were better able to master the skills required and made greater improvements…

In this article, the author offers two well-known mathematical images--that of a dot moving around a circle; and that of the tens chart--and considers their power for developing mathematical thinking. In his opinion, these images each contain the essence of a particular topic of mathematics. They are contrasting images in the sense that they deal…

In light of evidence indicating that errors in making accurate pie charts are prevalent, an alternative method for constructing pie charts is proposed. It involves the use of a simple trigonometric formula to compute a factor of the length of the chord that defines a given percentage sector. This factor is multiplied by the radius of the circle to…

By introducing elementary trigonometry earlier in a geometry course, a teacher can demonstrate how a variety of techniques can be brought to bear on the same problem. Eight theorems illustrate this. (Author/KM)