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Taylor polynomials in mathematica

• To: mathgroup at smc.vnet.net
• Subject: [mg108049] Taylor polynomials in mathematica
• From: Halla Gralla <feddera at hotmail.com>
• Date: Sun, 7 Mar 2010 04:04:35 -0500 (EST)

What I have is two unknown functions of b, x(b) and y(b). I do know their values in b=0, their first derivative and the value of their first derivatives in b=0.

x(0) = -c

x(0) = -d

x'(b) = (b*x(b) - 3*((y(b))^3) / (9(x(b))^2(y(b))^2 - b^2)

y'(b) = (b*y(b) - 3*((x(b))^3) / (9(x(b))^2(y(b))^2 - b^2)

it follows that:

x'(0) = c / 3d^2

y'(0) = d / 3x^2

Now I don't now how to find x''(b) or y''(b), which would be needed for a second ordered taylor polynomial, but mathematica knows (and perhaps does this automatically when setting up taylor polynomials?). Problem is, I don't know how to use mathematica very well. I need to make a "program" in mathematica where I can change values for n (order of taylor polynomial) and for c and d (which are constants in the functions).

Any help? =))

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  • Re: Taylor polynomials in mathematica
    • From: danl@wolfram.com