trigonomi

Trigonomi is a term used in some languages to denote the mathematical subject commonly known in English as trigonometry. It studies the relationships between the angles and sides of triangles and the functions that describe those relationships. Core concepts include the sine, cosine and tangent functions and their reciprocals, the unit circle, graphs and identities that relate these functions, and methods for solving triangles, both right-angled and oblique, using the laws of sines and cosines and inverse angle measures.

Historically, trigonomic ideas emerged from geometry and astronomy in ancient civilizations and were developed by Greek mathematicians such as Hipparchus and Ptolemy. They were further expanded in medieval Islamic mathematics and during the European Renaissance, culminating in the modern, analytic treatment that treats trigonometric functions as central objects in algebra and analysis.

Applications are widespread: surveying, navigation, astronomy, physics, computer graphics and vision, signal processing, acoustics, engineering, and architecture. In education, trigonomi is typically introduced to teach angle–side relationships, periodic functions, and their use in modeling periodic phenomena and rotating coordinate systems.

Terminology varies by language. In English, the standard term is trigonometry; trigonomi may appear as an alternative spelling or as the name of the subject in some languages or historical texts.

See also: Trigonometry; Unit circle; Laws of sines and cosines.