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Re: got stuck in equation

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Date Wed, 2 Jan 2013 04:44:46 +1100
Subject Re: got stuck in equation
From Chris Angelico <rosuav@gmail.com>
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On Wed, Jan 2, 2013 at 3:42 AM, Dave Angel <d@davea.name> wrote:
> On 01/01/2013 11:03 AM, Chris Angelico wrote:
>> This isn't a Python question, it's an algebra one. I don't know what
>> Z, S, and so on are, but for the most part, the basic rule of solving
>> equations applies: Do the same thing to both sides and it's still
>> true. Work on it until you can isolate SN on one side.
>
> Such a rule may not be able to solve an equation when there SN appears
> more than once on the RHS, and where it's inside a transcental
> function.  I don't consider this an algebra problem, but a programming
> problem.

It's a tad more complicated than your average equation, and I haven't
the time now to prove the point by actually solving it, but every
operation that I can see in that formula can be reversed. The hairy
bit is that there are two references to SN, so it's going to be a bit
messy to untangle, and might end up as a higher-order equation.

But you're likely right that other forms of solver may be more useful
here. Algebra definitely _could_ be the solution, but it isn't
necessarily the best.

ChrisA

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Thread

got stuck in equation usamazohad@gmail.com - 2013-01-01 07:40 -0800
  Re: got stuck in equation Chris Angelico <rosuav@gmail.com> - 2013-01-02 03:03 +1100
  Re: got stuck in equation Dave Angel <d@davea.name> - 2013-01-01 11:39 -0500
  Re: got stuck in equation Dave Angel <d@davea.name> - 2013-01-01 11:42 -0500
    Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 09:25 -0800
      Re: got stuck in equation Chris Angelico <rosuav@gmail.com> - 2013-01-02 04:51 +1100
      Re: got stuck in equation Ramchandra Apte <maniandram01@gmail.com> - 2013-01-01 21:20 -0800
        Re: got stuck in equation alex23 <wuwei23@gmail.com> - 2013-01-02 01:53 -0800
      Re: got stuck in equation Ramchandra Apte <maniandram01@gmail.com> - 2013-01-01 21:20 -0800
        Re: got stuck in equation DJC <djc@news.invalid> - 2013-01-02 14:44 +0000
    Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 09:25 -0800
      Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 09:30 -0800
      Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 09:30 -0800
      Re: got stuck in equation Roy Smith <roy@panix.com> - 2013-01-01 12:47 -0500
  Re: got stuck in equation Chris Angelico <rosuav@gmail.com> - 2013-01-02 04:44 +1100
    Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 10:00 -0800
      Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 10:12 -0800
      Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 10:12 -0800
    Re: got stuck in equation Usama Khan <usamazohad@gmail.com> - 2013-01-01 10:00 -0800
  Re: got stuck in equation Tim Roberts <timr@probo.com> - 2013-01-01 13:09 -0800

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