Circumconic with focus F
1) Let F* be the isogonal of F.
2) Let A*B*C* be the pedal triangle
of F*.
3) Let A1B1C1 be the intouch triangle
of A*B*C*.
4) The perpendicular from A to F*A1
and their analogs bound a triangle A'B'C'.
5) The requested conic is inscribed
in A'B'C' with focus F (construction c42).
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