Date: Nov 30, 2012 12:16 PM
Author: Marcio Barbalho
Subject: Re: Trouble finding the roots of an equation
"Nasser M. Abbasi" <nma@12000.org> wrote in message <k9aovn$loc$1@speranza.aioe.org>...

> On 11/30/2012 10:47 AM, Marcio Barbalho wrote:

> > Dear friends

> > salve salve!

> >

> > I'm trying to find n roots for this equation y = x*tan(x)-10.

>

> around where? here are some roots

>

> EDU>> x=-2*pi:.1:2*pi; %have a quick look first to get an idea

> EDU>> plot(x,x.*tan(x)-10)

> EDU>> sol=fsolve(@(x) x.*tan(x)-10,0.01:1:10);

> EDU>> sol'

>

> ans =

>

> 1.428870011214077

> 1.428870011214077

> 7.228109771675751

> 4.305801413119223

> 4.305801413119223

> 7.228109771627249

> 7.228109771627249

> 7.228109771627249

> 10.200262588295905

> 10.200262588295905

>

> >

> > It seems I'll have to include symbolic calculation, which I

> >was trying to avoid in order to speed up the processing!

> > So I wonder how I could transform y into a series and get n of its infinite roots.

> >

> > Any help will be very much appreciated!

> >

>

> --Nasser

Thank you very much, if you lived here I would buy you a beer. :)