grouping the variables in a certain way



Daniel Lakeland wrote:

> On Fri, Jun 15, 2007 at 06:26:29PM -0400, Kamaraju S Kusumanchi wrote:
>> 
>> Say I have
>> 
>> (%i5) a : D^2 * (D^2 - x^2)/(D+3*x)^4;
> ...
>> How can I change 'a' so that maxima displays
> ....
>> (%i6) b : (1-(x/D)^2)/(1+3*(x/D))^4;
> ...
>> Any ideas?
> 
> I love these kinds of questions, because I usually learn a lot about
> how to use maxima from them...
> 
> The only thing I can figure out is "by hand" methods. That is, telling
> maxima to carry out some operations. you can make this easier to do by
> using pickapart:
> 
> (%i36) pickapart(a,2);
> 
> 2
> (%t36)                                      D
> 
> 
> 2       2
> (%t37)                                    D  - x
> 
> 
> (%t38)                                    D + 3 x
> 
> %t36 %t37
> (%o38)                                   ---------
> 4
> %t38
> 
> (%i51) multthru(1/D^2,%t37)/multthru(1/D,%t38)^4;
> 
> 2
> x
> 1 - --
> 2
> D
> (%o51)                                  ----------
> 3 x      4
> (--- + 1)
> D
> 
> -----------------------------------------------------------------------
> 

This is working. Thanks. Any other solutions are also welcome.

raju

-- 
Kamaraju S Kusumanchi
http://www.people.cornell.edu/pages/kk288/
http://malayamaarutham.blogspot.com/