Difference between revisions of "Fermat point"

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The '''Fermat point''' (also called the Torricelli point) of a triangle <math>\triangle ABC</math> is a point <math>P</math> which has the minimum total distance to three [[vertices]] (i.e., <math>AP+BP+CP</math>).
 
The '''Fermat point''' (also called the Torricelli point) of a triangle <math>\triangle ABC</math> is a point <math>P</math> which has the minimum total distance to three [[vertices]] (i.e., <math>AP+BP+CP</math>).
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<asy>
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pair A=(2,4), B=(1,1), C=(6,1);
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pair pAB=rotate(60,B)*A, pCA=rotate(60,A)*C;
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path PC=pAB--C, PB=pCA--B;
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D(MP("A",A,2N)--MP("B",B,SW)--MP("C",C,SE)--cycle,green);
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D(C--pCA--A--pAB--B,red+dashed);
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DPA(PC^^PB,lightblue);
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D(MP("C'",pAB,NW),orange);
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D(MP("B'",pCA,NE),orange);
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D(A); D(B); D(C);
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D(MP("P",IP(PC,PB),E),blue);
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</asy>
  
 
==Construction==
 
==Construction==

Revision as of 05:02, 26 September 2014

The Fermat point (also called the Torricelli point) of a triangle $\triangle ABC$ is a point $P$ which has the minimum total distance to three vertices (i.e., $AP+BP+CP$).

[asy] pair A=(2,4), B=(1,1), C=(6,1);  pair pAB=rotate(60,B)*A, pCA=rotate(60,A)*C; path PC=pAB--C, PB=pCA--B; D(MP("A",A,2N)--MP("B",B,SW)--MP("C",C,SE)--cycle,green); D(C--pCA--A--pAB--B,red+dashed); DPA(PC^^PB,lightblue); D(MP("C'",pAB,NW),orange); D(MP("B'",pCA,NE),orange); D(A); D(B); D(C); D(MP("P",IP(PC,PB),E),blue); [/asy]

Construction

A method to find the point is to construct three equilateral triangles out of the three sides from $\triangle ABC$, then connect each new vertex to each opposite vertex, as these three lines will concur at first Fermat point.

See Also

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