Re: approximate functions in polynomial

*To*: mathgroup at smc.vnet.net*Subject*: [mg53921] Re: approximate functions in polynomial*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Fri, 4 Feb 2005 04:11:16 -0500 (EST)*Organization*: The University of Western Australia*References*: <ctnim6$f16$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In article <ctnim6$f16$1 at smc.vnet.net>, "Tun Myint Aung" <TMA at nus.edu.sg> wrote: > How can we approximate the following functions by polynomials ? > > f(a,b,c,d) = 1 / [ (a - b)^2 + (c - d)^2] > > I have tried to use Series in Mathematica but the result is complicated > and not close at all to the exact value if maximum power is 3. Exactly why do you want to do this? The intended application and some background would help. Clearly if a == b and c == d the function is infinite and not easy to approximate by a polynomials ... Cheers, Paul -- Paul Abbott Phone: +61 8 6488 2734 School of Physics, M013 Fax: +61 8 6488 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul