Outline of trigonometry


Trigonometry is a branch of mathematics that studies the relationships between the sides and the angles in triangles. Trigonometry defines the trigonometric functions, which describe those relationships and have applicability to cyclical phenomena, such as waves.


∠, the angle symbol in Unicode is U+2220
  • Geometry – mathematics concerned with questions of shape, size, the relative position of figures, and the properties of space. Geometry is used extensively in trigonometry.
  • Angle – the angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles formed by two rays lie in a plane, but this plane does not have to be a Euclidean plane.
  • Ratio – a ratio indicates how many times one number contains another

Content of trigonometry




Uses of trigonometry




Geography, geodesy, and land surveying



Analog devices


Other areas of mathematics

Geometric foundations

Trigonometric functions

Trigonometric identities

Trigonometric identity (list)

Solution of triangles

Solution of triangles

More advanced trigonometric concepts and methods

Numerical mathematics

Trigonometric tables

Trigonometric tables

Spherical trigonometry

Spherical trigonometry


mnemonics in trigonometry


See also

External links

  • An introduction to trigonometry
  • Benjamin Banneker's Trigonometry Puzzle at Convergence
  • Dave's short trig course
  • Trigonometric Delights, by Eli Maor, Princeton University Press, 1998. Ebook version, in PDF format, full text presented.
  • Trigonometry by Alfred Monroe Kenyon and Louis Ingold, The Macmillan Company, 1914. In images, full text presented.
  • Trigonometry FAQ
  • Trigonometry on Mathwords.com index of trigonometry entries on Mathwords.com
  • Trigonometry on PlainMath.net Trigonometry Articles from PlainMath.Net