Parametric equation

Representation of a curve by a function of a parameter

In mathematics, a parametric equation expresses several quantities, such as the coordinates of a point, as functions of one or more variables called parameters. In the case of a single parameter, parametric equations are commonly used to express the trajectory of a moving point. For this case, the parameter is often, but not necessarily, time, and the point describes a curve, called a parametric curve.

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