Ah, I see what you mean now.
In general representation, expressions of the form q^a*q^b are normalized
to q^(a+b). In particular, 7^(1/2)*7^(-1) is normalized to 7^(-1/2). Also,
q^(1/2) is displayed as sqrt(q) and q^(-1/2) as 1/sqrt(q) (with
sqrtdispflag=true, the default).
So sqrt(7)/7 is not considered simplified in general representation and
will be normalized to 7^(-1/2) == 1/sqrt(7)
-s
On Fri, Dec 20, 2013 at 6:49 PM, Ricardo JF <rcrdjf at hotmail.com> wrote:
> ok...thanks
> but is it possible get sqrt(7)/7 from n=1/sqrt(7)?
>
> .............
> n:1/sqrt(7);
>
> rat(n),algebraic; --->gives /R/ sqrt(7)/7
>
> ratdisrep(rat(n)), algebraic; --> should it be sqrt(7)/7? It
> gives 1/sqrt(7)!
>
> ratsimp(n),algebraic; --> It gives 1/sqrt(7)
> ..............
>
> ratsimp (with algebraic) sometimes makes nothing:
>
> ratsimp(1/sqrt(1-x^2)),algebraic; ---> gives -sqrt(1-x^2)/(x^2-1) (ok)
>
> ratsimp(1/sqrt(1+x^2)),algebraic; --> gives 1/sqrt(x^2+1) (the same)
>
>
> thanks
>
> ------------------------------
> Date: Fri, 20 Dec 2013 17:08:02 -0500
> Subject: Re: [Maxima] Rationalisation (very basic)
> From: macrakis at alum.mit.edu
> To: rcrdjf at hotmail.com
> CC: maxima at math.utexas.edu
>
>
> ratsimp(n) with algebraic:true also works.
>
>
> On Fri, Dec 20, 2013 at 5:05 PM, Stavros Macrakis <macrakis at alum.mit.edu>wrote:
>
> Yes, "algebraic" only works in the CRE package, so
> block([algebraic:true],ratdisrep(rat(n))) is what you want if you want a
> general representation result, as you say. Is there some problem you're
> having with that approach?
>
> -s
>
>
> On Fri, Dec 20, 2013 at 3:50 PM, Ricardo JF <rcrdjf at hotmail.com> wrote:
>
> how can i get the Rationalisation (general expression)?
>
> 1/sqrt(7) --> sqrt(7)/7
>
> ...........................
> n:1/sqrt(7);
>
> rat(n),algebraic; (CRE) ok
>
> ratdisrep(rat(n)), algebraic; (general expression)?
>
> ...........................
>
> thanks.
>
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