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From: "John D'Errico" <woodchips@rochester.rr.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: root finding of Linear equation
Date: Sat, 21 Nov 2009 09:43:10 +0000 (UTC)
Organization: John D'Errico (1-3LEW5R)
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Greg Heath <heath@alumni.brown.edu> wrote in message <727cae84-3988-4ae8-aaa7-cc73d80056e3@m33g2000vbi.googlegroups.com>...
> On Oct 29, 5:21?am, "John D'Errico" <woodch...@rochester.rr.com>
> wrote:
> > "Eldar " <el_os...@mynet.com> wrote in message <hcbncl$ao...@fred.mathworks.com>...
> > > I need to find out the roots of an any linear equation like;
> > > y = ax? + bx? + cx + d
> > > or
> > > y = ax? + bx + c
> >
> > > Any suggestions on how to approach such problem?
> > > Consider that I'm just new user of Matlab.
> >
> > In "ax? + bx? + cx + d", what is the ?
> > supposed to do?
> >
> > If these were meant to indicate a power
> > operation, then how is it that you call this
> > a LINEAR equation? It is nonlinear in the
> > variable of interest.
> 
> It's linear in the unknown coefficients which,
> given data, can be solved using backslash.
> 
> Greg

NO. You can solve for the coefficients using
backslash.

But you cannot solve for the roots of an equation
using backslash!

You can use fzero to find a root, or roots to find
the roots if the equation is quadratic, as it appears
to be.

John