Sunday, April 11, 2021

1686. A Property of OI line

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1 comment:

  1. Dr. Abdilkadir AltıntaşApril 17, 2021 at 8:19 PM

    If P' is the isogonal conjugate of Q wrt DEF, then P' lies on OI.

    The mapping P-> P' is a projective transformations on the line OI and its fixed points are X(3513) and X(3514).


    Angel Montedeoca

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