Most trigonometry students look at triangles on a flat surface. However, people from ancient astronomers to modern navigators calculated the arc lengths and angles of triangles on a sphere. They used ...

The adjacent side (\(a\)) is next to the angle in question (\(x\)). The trigonometric ratios for the angles 30°, 45° and 60° can be calculated using two special triangles. An equilateral ...

For students between the ages of 11 and 14. Introduction to trigonometry for right-angled triangles Learn about three trigonometric ratios in similar right-angled triangles with this BBC Bitesize ...