> The general simplifier does (1-x)^a/(1-x) --> (1-x)^(a-1), but it *doesn't
> *convert (1-x)^a/(x-1) --> -(1-x)^(a-1).
> I don't know of any simplification function that does (1-x)^a/(x-1) -->
> -(1-x)^(a-1):
Using box does the job
aux: (1-x)^a/(x-1);
aux: ratsubst(box(1-x),1-x,aux);
rembox(%);
(%o1) (1-x)^a/(x-1)
(%o2) -(1-x)^(a-1)
(%o3) -(1-x)^(a-1)
aux: (1-x)^a/(1-x);
aux: ratsubst(box(1-x),1-x,aux);
rembox(%);
(%o4) (1-x)^(a-1)
(%o5) (1-x)^(a-1)
(%o6) (1-x)^(a-1)
Best
________________________________________________________________
Jose Sanchez-Marin.
Universitat de Valencia.
Institut de Ciencia Molecular (ICMol).
Cat. Jose Beltran Martinez, 2 Phone: +34 96 354 4444
E-46980 Paterna FAX: +34 96 354 3576
Spain e-mail: Jose.Sanchez at uv.es
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