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cardioid

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noun car·di·oid \ˈkär-dē-ˌȯid\

Definition of cardioid

  1. :  a heart-shaped curve that is traced by a point on the circumference of a circle rolling completely around an equal fixed circle and has an equation in one of the forms ρ = a(1 ± cos θ) or ρ = a(1 ± sin θ) in polar coordinates



Illustration of cardioid

1753

First Known Use of cardioid

1753


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