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Find the partition of a triangle into cevian triangles with congruent incircles
ResourceFunction["CongruentIncirclePartition"][{p1,p2,p3},n] partition a triangle defined by vertices p1,p2 and p3 into cevian triangles that share vertex p1 and the same inradius. |
| "Partitions" | The number n of cevian triangles |
| "Inradius" | The radius of the incircle in each cevian triangle |
| "Incircles" | The congruent incircles |
| "CevianEndpoints" | The vertices of each cevian triangle other than p1 on segment p2p3 |
| "CevianTriangles" | Cevian triangles from by p1and two adjacent in "CevianEndpoints" |
Return an association containing the information of a partition of a given triangle into subtriangles sharing incircles of same size:
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Find a cevian partition of a given triangle into 7 triangle with incircles of same size:
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For each orientation, find a 4-part cevian partition:
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Certain triangles with integral sides also have integral inradii in a cevian triangle partition:
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The number of partition must be at least 2. Otherwise the function returns unevaluated:
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Degenerate triangles are not supported. The function returns unevaluated:
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Perturb one vertex to create a non-degenerate case:
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Coordinates must be real numeric values. Otherwise the function returns unevaluated:
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Given an arbitrary triangle, let n-1 cevians be drawn from one of its vertices so all of the n triangles so determined have equal incircles. Then the incircles determined by spanning 2, 3,…, n-1 adjacent triangles are also equal (Wells 1991, p. 67). For instance, a spanning set of size 2:
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Check the inradii:
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Visualize the cevian triangles and the incircles:
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Show the same result for spanning 3 adjacent intervals:
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The observation follows this general argument: in triangle TSR if two cevian triangles TSU and TVR have the same inradius, so do triangles TSV and TUR:
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Visually verify the argument:
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Wolfram Language 14.0 (January 2024) or above
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