Cardioid Evolute
CardioidEvolute
x = cost(1+cost)
(1)
y = sint(1+cost)
(2)
is the curve
x_e = 2/3a+1/3acostheta(1-costheta)
(3)
y_e = 1/3asintheta(1-costheta),
(4)
which is a mirror-image cardioid with a^'=a/3.
See also
Cardioid, Cardioid Involute, EvoluteExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Cardioid Evolute." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/CardioidEvolute.html