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Re: Separating square roots

• To: mathgroup at smc.vnet.net
• Subject: [mg127252] Re: Separating square roots
• From: Murray Eisenberg <murray at math.umass.edu>
• Date: Wed, 11 Jul 2012 02:21:03 -0400 (EDT)
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• Reply-to: murray at math.umass.edu

Here's a way, which is probably unnecessarily verbose.

   a = 3 + 5 x^2 + 7 x + Sqrt[5 + x] + 7 x Sqrt[5 + x];
   terms = List @@ a;
   Plus @@ Pick[terms, FreeQ[#, Sqrt[_]] & /@ terms]

On 7/10/12 12:42 AM, rhartley.anu at gmail.com wrote:
> I have an expression which is a sum of terms, some monomials
> and others involving square roots, such as
> A = 3  + 5 x^2 + 7 x + Sqrt[5+x] + 7 x Sqrt[5+x] (but much more complicated).
> I want to solve this, which involves separating terms with the square root
> from those that do not have a square root, then squaring each.
>
> I can not work out how to separate out those terms that have the square
> root.  I do not want to hard code, such as nosqrt = A[[1]] + A[[2]] , etc.
> Can anyone help?


-- 
Murray Eisenberg                     murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
710 North Pleasant Street            fax   413 545-1801
Amherst, MA 01003-9305

• References:
  • Separating square roots
    • From: rhartley.anu@gmail.com