In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for...

Pythagorean trigonometric identity, also called simply the Pythagorean identity, is an identity expressing the Pythagorean theorem in terms of trigonometric functions...

are several equivalent ways for defining trigonometric functions, and the proofs of the trigonometric identities between them depend on the chosen definition...

Brahmagupta–Fibonacci identity or Cassini and Catalan identities Heine's identity Hermite's identity Lagrange's identity Lagrange's trigonometric identities List of logarithmic...

earliest-known tables of values for trigonometric ratios (also called trigonometric functions) such as sine. Throughout history, trigonometry has been applied...

Many identities interrelate the trigonometric functions. This section contains the most basic ones; for more identities, see List of trigonometric identities...

In trigonometry, it is common to use mnemonics to help remember trigonometric identities and the relationships between the various trigonometric functions...

how many times one number contains another Trigonometry Trigonometric functions Trigonometric identities Euler's formula Archimedes Aristarchus Aryabhata...

function is replaced with a trigonometric one. Trigonometric identities may help simplify the answer. Like other methods of integration by substitution...

functions List of integrals of inverse trigonometric functions List of trigonometric identities Trigonometric function Trigonometric functions of matrices...