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Re: Calculating derivate in Mathematica 9 giving wrong

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  • Subject: [mg131416] Re: Calculating derivate in Mathematica 9 giving wrong
  • From: "Louis Talman" <talmanl at gmail.com>
  • Date: Wed, 3 Jul 2013 22:01:02 -0400 (EDT)
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  • References: <20130703090146.A8EAD6AD9@smc.vnet.net>

Asking for the derivatives of the same expressions might give you the  
same, or at least equivalent, results.

On Wed, 03 Jul 2013 03:01:46 -0600, James <jhlawley at gmail.com> wrote:

> In[5]:= D[(x^2 - 2)/(x^3 + 6), x]
> Out[5]= -((3 x^2 (-2 + x^2))/(6 + x^3)^2) + (2 x)/(6 + x^3)
> That is from Mathematica 9.
> The wolfram alpha site and my textbook give this answer:
> d/dx((x^2+x-2)/(x^3+6)) = (-x^4-2 x^3+6 x^2+12x+6)/(x^3+6)^2
> Please tell me what I am doing wrong.

--Louis A. Talman
   Department of Mathematical and Computer Sciences
   Metropolitan State University of Denver

   <http://rowdy.msudenver.edu/~talmanl>



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