An adjoint curve which bears a special relation to the base curve.
Phi Curve
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References
Coolidge, J. L. A Treatise on Algebraic Plane Curves. New York: Dover, p. 310, 1959.Referenced on Wolfram|Alpha
Phi CurveCite this as:
Weisstein, Eric W. "Phi Curve." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/PhiCurve.html