The inverse curve of the Maclaurin trisectrix with inversion center at the negative -intercept is a Tschirnhausen cubic.
Maclaurin Trisectrix Inverse Curve
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Cite this as:
Weisstein, Eric W. "Maclaurin Trisectrix Inverse Curve." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/MaclaurinTrisectrixInverseCurve.html