New Properties of Triangular Orbits in Elliptic Billiards

New invariants in the family of 3-periodics in an Elliptic Billiard (EB) were introduced in [20], stemming from both experimental and theoretical work. These include relationships between radii, angles and areas of triangular members of the family, as well as a special stationary circle. Here we present the proofs promised there as well as a few new related facts.

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