Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2001

[Date Index] [Thread Index] [Author Index]

Search the Archive

AW: Exponential Equations

  • To: mathgroup at smc.vnet.net
  • Subject: [mg28832] AW: [mg28792] Exponential Equations
  • From: Matthias.Bode at oppenheim.de
  • Date: Tue, 15 May 2001 00:59:03 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Phil,

IN:
Solve[3^(2 x) == (1/9)^(x + 5), x];
N[%]
OUT:
Solve::"ifun": "Inverse functions are being used by \!\(Solve\), so some \
solutions may not be found."

{{x -> -2.5 + 1.4298 \[ImaginaryI]}, 
{x -> -2.5 - 1.4298 \[ImaginaryI]},
{x -> -2.5 - 2.8596 \[ImaginaryI]},
{x -> -2.5}}

The last result appears to be the one you expected.

Sincerely,

Matthias Bode
Sal. Oppenheim jr. & Cie. KGaA
Koenigsberger Strasse 29
D-60487 Frankfurt am Main
GERMANY
Tel.: +49(0)69 71 34 53 80
Mobile: +49(0)172 6 74 95 77
Fax: +49(0)69 71 34 6380
E-mail: matthias.bode at oppenheim.de
Internet: http://www.oppenheim.de



"Why can't Mathematica find x = -5/2 when executing the following? Is
there a package I should load? It seems so simple.

Solve[3^(2 x)==(1/9)^(x + 5),x]"



  • Prev by Date: Re: don't understand #
  • Next by Date: Re: Problem overriding simple built-in functions
  • Previous by thread: webMathematica Hosting Service
  • Next by thread: Re: column * row ??(2)