Robot Fermat point
This activity belongs to the GeoGebra book Attractive projects.
2D project: create automatic dynamic demonstrations.
In this other example, we want to find the Fermat point of a given triangle. For this, we have replaced the paper of the vertex C of the triangle and its alter ego C0 by a point outside the triangle: F and F0.
Now, the goal is to minimize the expression dif = abs(F - A) + abs(F - B) + abs(F - C).
In this case, the "process done" message will appear when the increment is undistinguishable from 0 (without using the GeoGebra CAS).
Author of the construction of GeoGebra: Rafael Losada