Re: Viewing real solution out of Root[#] output

• To: mathgroup at smc.vnet.net
• Subject: [mg50658] Re: Viewing real solution out of Root[#] output
• From: Paul Abbott <paul at physics.uwa.edu.au>
• Date: Wed, 15 Sep 2004 07:54:30 -0400 (EDT)
• Organization: The University of Western Australia
• References: <ci8mmt\$bsj\$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

In article <ci8mmt\$bsj\$1 at smc.vnet.net>, mbekkali at gmail.com (Mukhtar)
wrote:

> Is there a way to view the real solution (no matter how many pages it
> would take just to print it) for output of the form something like
> Root[x#1+2x#1-3#2] and so on, where x is some symbolic parameter?

As an example,

ToRadicals[Root[#^3 - #^2 + 1 & , 1]]

Note that some expressions cannot be expressed as radicals. For example,

Root[#^5 - # + 1 & , 1]

Section 3.4.3 of the Mathematica book states that:

However, you should realize that there are some special cases in which
a reduction to radicals is in principle possible, but Mathematica
cannot find it. The simplest example is the equation

x^5 + 20 x + 32 == 0

And I must still ask, why do you want to view the real solution,
especially if it takes many pages to print out, and what do you want to
do with it?

Cheers,
Paul

--
Paul Abbott                                   Phone: +61 8 9380 2734
School of Physics, M013                         Fax: +61 8 9380 1014
The University of Western Australia      (CRICOS Provider No 00126G)
35 Stirling Highway
Crawley WA 6009                      mailto:paul at physics.uwa.edu.au
AUSTRALIA                            http://physics.uwa.edu.au/~paul

• Prev by Date: Re: Viewing real solution out of Root[#] output
• Next by Date: Re: anyone else have same problems? partition grahics
• Previous by thread: Re: Viewing real solution out of Root[#] output
• Next by thread: Re: Viewing real solution out of Root[#] output