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AW: Exponential Equations


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]"



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