(%i3) ratsimp((4715*7^(3/2)+87472) / (59460*sqrt(7)+157710)),algebraic : true;
(%o3) (sqrt(7)+14)/30
--Barton
________________________________
From: maxima-bounces at math.utexas.edu [maxima-bounces at math.utexas.edu] on behalf of Alasdair McAndrew [amca01 at gmail.com]
Sent: Sunday, April 14, 2013 21:04
To: maxima list
Subject: Simplifying fractions with radicals?
I recently had this expression:
(4715*7^(3/2)+87472) / (59460*sqrt(7)+157710)
returned as the solution to a set of non-linear equations. Now by multiplying numerator and denominator by
59460*sqrt(7)-157710
and simplifying with radcan, this expression simplifies to
(\sqrt(7)+14)/30
which is far simpler. But is there any more direct way of simplifying such an expression? Or, is there any way of obtaining the expression
59460*sqrt(7)-157710
from the original output, without either copying or pasting, or fiddling about with parts of expressions? I mean, if
b:(4715*7^(3/2)+87472) / (59460*sqrt(7)+157710);
then I could write
c:part(b,2,1)-part(b,2,2);
and then
radcan(radcan(num(b)*c)/radcan(denom(b)*c));
This works fine - but I'm wondering if there's a more direct way.
--
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