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# Solving a System of Equations in Real Range in MAthCAD

## Solving a System of Equations in Real Range in MAthCAD

(OP)
Is it possible to solve a system of nonlinear equations in real range in MAthCAD??

I know how to solve an equation in real range, but system doesn't...

### RE: Solving a System of Equations in Real Range in MAthCAD

Not symbolically.   I would use minerr to minimize residuals.  What are your equations?

Peter Nachtwey
Delta Computer Systems
http://www.deltamotion.com

### RE: Solving a System of Equations in Real Range in MAthCAD

(OP)
I have system of four algebraical nonlinear equations.

I have found the solution, but it takes a lot of time,
because of presence of complex roots along with real roots.

I need only real solutions of system, so the question is
how to make MathCAD finds only real roots....

I know how to do that with single equation. (assume, x=real)
But I have no idea how to do that with an system of equations.....

### RE: Solving a System of Equations in Real Range in MAthCAD

Mathcad can manange some symbolic solutions of non-linear equations, but it is still only a computer programme so can't work miracles. But it can try a lot of methods and approaches so will have a go. It does help if you have a good idea of the sort of answer you would expect. It is easy to make the system of equations just that little bit too fancy and as a consequence loose all chance of a solution.

You also have to beware of MuPad's German origins, so while it has precision, it can also be pedantic. Maple appears to have the opposite American view, often providing the 'common' answer, even if it is wrong (think integral (1/x) passing through zero..)

Start with a system of 2 equations, and build up to three, then four.

### RE: Solving a System of Equations in Real Range in MAthCAD

taketo,

Do you have a worksheet that you can post for us to look at?

Pete

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