Definition:Trigonometry

Definition

Trigonometry is the branch of mathematics which studies the relationships between the lengths of sides and angles of triangles.

Spherical Trigonometry

Spherical trigonometry is the branch of mathematics which concerns the measurement of spherical triangles and related figures on the surface of a sphere.

Also see

• Results about trigonometry can be found here.

Historical Note

The field of trigonometry emerged in ancient Greece during the $3$rd century BCE from applications of geometry to astronomical studies.

While the Greeks focused on the calculation of chords, mathematicians in India created the earliest-known tables of values for trigonometric functions such as sine.

An analytic approach to Trigonometry was introduced by Leonhard Paul Euler.

Linguistic Note

The word trigonometry derives from the Greek trigōnon (triangle) and metron (measure), literally meaning measurement of triangles.