Definition:Trigonometric Function

There are six basic trigonometric functions: sine, cosine, tangent, cotangent, secant, and cosecant.

= Sine =

= Cosine =

= Tangent =

The tangent function is usually defined as the ratio $$\frac{sine}{cosine}$$.

See the definition of the tangent function for a fuller discussion.

= Cotangent =

The cotangent function is usually defined as the ratio $$\frac{cosine}{sine}$$.