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Re: How to use Mathematica find the solution of an

• To: mathgroup at smc.vnet.net
• Subject: [mg130898] Re: How to use Mathematica find the solution of an
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Fri, 24 May 2013 06:23:57 -0400 (EDT)
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The equation does not appear to have a solution except as a limit (from
below) but then the solution is either -1 or 1.


eqn = Arg[-(I/((1 + I w)^2 w))] == -Pi;


eqn // Simplify


False


eqn /. {{w -> -1}, {w -> 1}}


{False, False}


Limit[Arg[-(I/((1 + I w)^2 w))],
  w -> -1, Direction -> 1] == -Pi


True


Limit[Arg[-(I/((1 + I w)^2 w))],
  w -> 1, Direction -> 1] == -Pi


True



Bob Hanlon




On Thu, May 23, 2013 at 4:04 AM, Eduardo M. A. M. Mendes <
emammendes at gmail.com> wrote:

> Hello
>
> I need to solve the following equation:
>
> Arg[-(I/((1+I \[Omega])^2 \[Omega]))]==-\[Pi]
>
> I have tried Solve (empty output), Reduce (it gives some results but not
> the answer Omega=1) and FindRoot (it gives Omega=1 but it is a
> numerical search).   Is there a way to get the solution not using a
> numerical search?
>
> Many thanks
>
> Ed
>
> PS.   I need to solve several equation of the same kind.
>
>

• Follow-Ups:
  • Re: How to use Mathematica find the solution of an
    • From: "Eduardo M. A. M. Mendes" <emammendes@gmail.com>

• References:
  • How to use Mathematica find the solution of an equation when Arg is part of it?
    • From: "Eduardo M. A. M. Mendes" <emammendes@gmail.com>