Re: Differentiation and Polynomial questions

• To: mathgroup at smc.vnet.net
• Subject: [mg20718] Re: Differentiation and Polynomial questions
• From: "Allan Hayes" <hay at haystack.demon.co.uk>
• Date: Wed, 10 Nov 1999 00:17:37 -0500
• References: <805vjq\$ddu@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Danny:

Answers to you first two questions are in the following notebook.
To see it properly formatted,
-- copy from "Notebook" down to the final "]" (just short of the line of
stars)
-- open up a Mathematica Notebook
-- past into the notebook
( a new notebook will be generated from the copied code)

Allan
---------------------
Allan Hayes
Mathematica Training and Consulting
Leicester UK
www.haystack.demon.co.uk
hay at haystack.demon.co.uk
Voice: +44 (0)116 271 4198
Fax: +44 (0)870 164 0565

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We can change the code of (a copy of)  Step by Step Differentiation to give
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so that \"QuotientRule\" comes before, and so is used before, \
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We get\
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********************************************************************

Danny Mathews <dmathews at ticnet.com> wrote in message
news:805vjq\$ddu at smc.vnet.net...
> I was using the "StepbyStepDifferentiation" package I found on the web
site
> and it has raised a question for me.
>
> It seems that Mathematica ignores the Quotient Rule in general and uses
the
> Product Rule for equations in a f(x)/g(x) format.
>
> This leaves the solution in a f(x) + g(x) format that I have to simplify
to
> get the answer to agree with what I came up with using a pencil or on my
> TI-89 calculator.
>
> An example is (1+x^2)/(1-x^2).  I came up with(as did my TI-89)
> 4x/((x^2-1)^2) for a solution.
>
> Mathematica gives a answer in the form of f(x) + g(x) that will simplify
to
> the solution above.  I tried several examples with the same scenario.  Is
>
> Also, Mathematica displays polynomials with the powers written in
ascending
> order which is opposite of how I was taught to write polynomials in
standard
> form.  Can this be changed?
>
> Bonus Question:
>
> My Calculus instructor loves piece-wise functions.  Any info on plotting
>
> Regards,
> Danny Mathews
>
>
>

```

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