       Re: Solving simultaneous eqns

• To: mathgroup at smc.vnet.net
• Subject: [mg14243] Re: Solving simultaneous eqns
• From: Paul Abbott <paul at physics.uwa.edu.au>
• Date: Mon, 12 Oct 1998 13:51:28 -0400
• Organization: University of Western Australia
• References: <6vf3ta\$dde@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Yeoung-Sang Yun wrote:

> I want to know how to solve the following simulaneous equations in
> Mathematica:
>
> x=x^1.2/(2*x^3+y^0.7+4*z^2.5)
> y=y^0.7/(2*x^0.6+y^2+z^2.2)
> z=0.9*z^1.5/(x^0.7+2*y^0.2+z^1.1)

Closed form solution is unlikely.  Here is one way to find a numerical
solution using FindRoot:

In:= Chop[FindRoot[{
x == x^1.2/(2*x^3 + 4*z^2.5 + y^0.7),
y == y^0.7/(z^2.2 + y^2 + 2*x^0.6),
z == (0.9*z^1.5)/(z^1.1 + x^0.7 + 2*y^0.2)},
{x, 1}, {y, 1.5}, {z, 2}]]

Out= {x->0.207116,y->0.61566,z->0}

Cheers,
Paul

____________________________________________________________________
Paul Abbott                                   Phone: +61-8-9380-2734
Department of Physics                           Fax: +61-8-9380-1014
The University of Western Australia            Nedlands WA  6907
mailto:paul at physics.uwa.edu.au  AUSTRALIA
http://www.physics.uwa.edu.au/~paul

God IS a weakly left-handed dice player
____________________________________________________________________

```

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