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Old 18-11-2010, 03:10 PM
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Robh (Rob)
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Join Date: Feb 2009
Location: Blue Mountains, Australia
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Quote:
Originally Posted by sjastro View Post

If you use Mathis' geometrical step construction you will in fact find the sum of the lengths of the hypotenuses of the sub triangles is a constant value irrespective of the number of sub triangles used.
I didn't find any reference to this constancy, which is patently ridiculous as sqr(x1^2+y1^2)+sqr(x2^2+y2^2)<>sqr( (x1+x2)^2+(y1+y2)^2). The fact is that the length of any curve can be obtained by integrating ds where ds^2=dx^2+dy^2.
dx and dy can be considered the horizontal and vertical components of an infinitesimally small right triangle drawn on the section of curve. His assumption that ds=dx+dy is a clear contradiction of Pythagoras' Theorem. As I mentioned before ds<dx+dy for all right-triangles on the curve. His assumptions are unjustifiable.

Regards, Rob
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