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Topic: Finding roots of cubic symbolic polynomials
Replies: 8   Last Post: Aug 13, 2014 10:54 AM

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 Steven Lord Posts: 2,237 Registered: 9/26/13
Re: Finding roots of cubic symbolic polynomials
Posted: Aug 13, 2014 10:19 AM

"Sanaa " <findingsanaa@yahoo.com> wrote in message
news:lsfq53\$on1\$1@newscl01ah.mathworks.com...
> "Steven Lord" <Steven_Lord@mathworks.com> wrote in message
> <lsfpp6\$nim\$1@newscl01ah.mathworks.com>...

>>
>> "Sanaa " <findingsanaa@yahoo.com> wrote in message
>> news:lsfopu\$kg6\$1@newscl01ah.mathworks.com...

>> > "Nasser M. Abbasi" wrote in message <lsflaa\$k11\$1@speranza.aioe.org>...
>> >> On 8/13/2014 7:08 AM, Sanaa wrote:
>> >> > Hi,
>> >> > I need to calculate the roots of a cubic symbolic polynomials. It
>> >> > contains 7 parameters.
>> >> > Any help is appreciated.
>> >> > Thank you
>> >> >

>> >>
>> >> help solve

>> > function sols = solve_cubic( segma, beta, mu, nu, delta, gamma)
>> > syms lambda sols =
>> > solve(lambda^3+lambda^2*(nu*mu+delta*mu+gamma*mu+segma*beta*mu+mu^2)+lambda*(delta*mu^2+gamma*mu^2+nu*gamma*mu+segma*gamma*mu-segma*mu*beta))
>> > end

>>
>> Show the group EXACTLY how you called solve_cubic and the FULL text of
>> any error or warning messages you received. The group should be able to
>> call solve_cubic using ONLY your instructions on how to call it.
>>
>> --
>> Steve Lord
>> slord@mathworks.com
>> http://www.mathworks.com

>
> In the command window, I typed
> sols = solve_cubic( segma, beta, mu, nu, delta, gamma)

When I execute that command, I receive this error:

>> sols = solve_cubic( segma, beta, mu, nu, delta, gamma)
Undefined function or variable 'segma'.

Therefore you have NOT given the group enough instructions to call
solve_cubic as I requested. Until you do, I don't think anyone in the group

--
Steve Lord
slord@mathworks.com
http://www.mathworks.com

Date Subject Author
8/13/14 Sanaa
8/13/14 Nasser Abbasi
8/13/14 Sanaa
8/13/14 Nasser Abbasi
8/13/14 Steven Lord
8/13/14 Sanaa
8/13/14 Steven Lord
8/13/14 Sanaa
8/13/14 Nasser M. Abbasi