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  1. Nine-point Circle
    1. Nine-point Circle (Part 1)
    2. Nine-point Circle (Part 2)
    3. Nine-point Circle (Part 3)
    4. Nine-point Circle (Part 4)
    5. Feuerbach's Theorem
    6. 16 Points of Tangency

Nine-point Circle

Author:Alex CHIK
Topic:Circle
script of a talk by Mr. C.K. Leung on 25/4/2015 cover picture taken from http://www-history.mcs.st-and.ac.uk/Mathematicians/Feuerbach.html GeoGebra 互動數學教室 http://www.geogebra.hk

  • Nine-point Circle (Part 1)

  • Nine-point Circle (Part 2)

  • Nine-point Circle (Part 3)

  • Nine-point Circle (Part 4)

  • Feuerbach's Theorem

  • 16 Points of Tangency

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Nine-point Circle (Part 1)

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