The Feuerbach Theorem and the Feuerbach Point

The Feuerbach Theorem states that the nine-point circle is internally tangent to the incircle and externally tangent to the three excircles. The Feuerbach point is the point of tangency between the incircle and nine-point circle.

 

Steve Phelps

 
資源型態
活動
標籤
geometry  triangle 
適合年齡
14 – 18
語言
English
 
 
 
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