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Subject: Re: length of the arc
Date: Thu, 15 Mar 2012 01:45:17 +0000 (UTC)
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"rsch tosh" wrote in message <jjquno$knf$1@newscl01ah.mathworks.com>...
> y=x^3/25-3*x^2/625-2*x/15625
> I want to find the length of this equation using matlab.
- - - - - - - - -
  The integral that gives the arc length of your curve is known in general as an "elliptic integral".  As Nasser has shown, in your case it is the integral of the square root of a certain quartic polynomial.  See:

 http://mathworld.wolfram.com/EllipticIntegral.html,   and
 http://en.wikipedia.org/wiki/Elliptic_integral

for a discussion.  Elliptic integrals first became of interest in the problem of finding arc length along an ellipse, hence the name. 

Roger Stafford