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Re: silly questions?

• To: mathgroup at smc.vnet.net
• Subject: [mg59091] Re: silly questions?
• From: dh <dh at metrohm.ch>
• Date: Thu, 28 Jul 2005 02:27:53 -0400 (EDT)
• References: <dc77me$k74$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Hi Kent,
obviously, Mathematica considers
(x^5-32)/(x-2) simplier than
16 + 8*x + 4*x^2 + 2*x^3 + x^4
Why?
Consider that Mathematica must have some function to value the complexity of an 
expression. This function is called: "ComplexityFunction" and by default 
  counts the leafs. That explains the above. You may change this 
behaviour by specifying another function, see Help.

sincerely, Daniel

Kent Holing wrote:
> Why does not (x^5-32)/(x-2)//FullSimplify in Mathematica  work?
> Compare with Factor[x^5-32]//InputForm which returns (-2 + x)*(16 + 8*x + 4*x^2 + 2*x^3 + x^4).
> So why does not the first command just return 16 + 8*x + 4*x^2 + 2*x^3 + x^4?
> As in a factorization above, how is the easiest way to pick automatically (by a function) the factors of say degree >=2,  if any ?
> 
> Kent Holing
>