[Newbie:] How to discard higher orders of variables?
Subject: [Newbie:] How to discard higher orders of variables?
From: Schirmacher, Rolf
Date: Thu, 12 Jul 2007 09:59:52 +0200
Hello Daniel,
> -----Original Message-----
> From: maxima-bounces at math.utexas.edu
> [mailto:maxima-bounces at math.utexas.edu]On Behalf Of Daniel Lakeland
> Sent: Thursday, July 12, 2007 12:13 AM
> To: maxima at math.utexas.edu
> Subject: Re: [Maxima] [Newbie:] How to discard higher orders of
> variables?
>
< some old introduction omitted >
>
>
> Another thing I tried:
>
> taylor(det,beta,0,2);
>
Here i get
(%i29) factor(taylor(det,beta,0,2));
(%o29)
-(2*Omega^6-2*beta^2*kappa^4*Omega^4+3*nu*beta^2*kappa^2*Omega^4-3*beta^2*ka
ppa^2*Omega^4+
~~~~~~~~~
nu*kappa^2*Omega^4-3*kappa^2*Omega^4-2*beta^2*Omega^4-2*Omega^4-nu*beta^2*ka
ppa^6*Omega^2+
~~~~~~~~~~~~~~~~~~~~~~~~~~
3*beta^2*kappa^6*Omega^2-7*nu*beta^2*kappa^4*Omega^2+3*beta^2*kappa^4*Omega^
2-nu*kappa^4*Omega^2+
kappa^4*Omega^2-4*nu*beta^2*kappa^2*Omega^2+6*beta^2*kappa^2*Omega^2-2*nu^2*
kappa^2*Omega^2-
nu*kappa^2*Omega^2+3*kappa^2*Omega^2+nu*beta^2*kappa^8-beta^2*kappa^8-2*nu^2
*beta^2*kappa^6+
2*nu*beta^2*kappa^6-3*nu^3*beta^2*kappa^4+3*nu^2*beta^2*kappa^4+4*nu*beta^2*
kappa^4-4*beta^2*kappa^4-
nu^3*kappa^4+nu^2*kappa^4+nu*kappa^4-kappa^4)/2
All terms underlined with ~~~~ are those not containing kappa^2. So, we
might argue that they are all Omega^4 or higher, but at least they are
there...
> This has a factor of kappa^2 multiplying it, so eliminate that:
>
> expr:ratsimp(%/kappa^2,beta);
>
< rest of original mail omitted >
Did we get different results or did I do something wrong?
Rolf