The word ‘trigonometry’ is formed by two Greek words, “trigonon” and “metron”, where “trigonon” means triangle and “metron” means measurement. Trigonometry is a branch of mathematics that deals with measurement of sides and angles of a triangle, and the relationship between them. It plays an important role in various fields such as architecture, astronomy, engineering, etc.

Opening Problem

A passenger in an airplane at an altitude of 10 kilometers sees two ships directly to the east of the plane. The angle of depression to the ships are 600 and 300 as shown in. How far apart are the ships?