# trigonometry

## Computing an Angle in an Equilateral Triangle

The following geometry problem is simple to state but challenging to solve!

## Some Down-to-Earth Trigonometry

This article aims to present some applications of trigonometry to earth sciences. We assume that the earth is a perfect sphere.

## Geometric Proof of a Trigonometric Identity

The following diagram is a “proof without words” (also known as a ‘visual proof’) for the trigonometric identity.

## Creating Trigonometric Tables

Have you tried to create your own trigonometric tables and thus join the likes of several mathematician astronomers of the past who created tables of trigonometric functions for their astronomical calculations?

## Area, Perimeter and Congruency

The topic of Perimeter and Area provides rich ground for teachers to examine the truth values of statements and then introduce the crucial ‘What-If ’ which can change a situation around completely.

## Trisection of a 60 degree angle? Not Quite!

CoMaC discusses with us the trisection of angles and shows us its proof in a non-computational way.

## Explorations in Teaching

In this short note we describe some incidents in mathematics teaching— as they actually occurred in the classroom.

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