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We all know that a curve to two points with same sum of distances is ellipse.
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But how about to 3 points?
I try to study this case as I haven't find out any mention about it.
My study show that the curve is interesting, I start from ths most simple case:
3points in one line and with equal distance c , the sum of the distance is p and one important figure is, p=3c,
another important figure is p=2c which is limitation of the p. if p=2c, that means the curve is a point.
figure1 is p<3c,>> 2c,
figure 2 is p=2c,which like an eye
figure 3 is p>3c, similar as fig1
figure 4 is p very close to 2c, which like a ellipse
the blue curve is real curve and brown curve is ellipse which simply for reference.