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Subject: Re: Nonlinear system of equations
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Xref: news.mathworks.com comp.soft-sys.matlab:712730

On 26/02/11 4:04 AM, Milos Milenkovic wrote:

> I have the following system of nonlinear equations
>
> (a*c*h-a*b*c)/b^2+n/2=0
>
> (a*c*k^2/3-a*b*c*h+a*c*h^2+a*b*m)/b^3-n/2=0
>
> variables are h and b, other are constants.
>
> There is a way to solve it in MATLAB?

Yes with the symbolic toolkit.

syms a b c h k m n
solve([(a*c*h-a*b*c)/b^2+n/2, 
(a*c*k^2/3-a*b*c*h+a*c*h^2+a*b*m)/b^3-n/2], h, b)

The answer involves b being the roots of a quartic, and h being an 
expression of the form (1 - f*b)*b where f is a relatively simple ratio 
involving some of the constants.