\begin{definition}[Definition:Folium of Descartes/Parametric Form]
The '''folium of Descartes''' is the locus of the equation given in parametric form as:
:$\begin {cases} x = \dfrac {3 a t} {1 + t^3} \\ y = \dfrac {3 a t^2} {1 + t^3} \end {cases}$
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\end{definition}