Inverse function warnings
- To: mathgroup at smc.vnet.net
- Subject: [mg99164] Inverse function warnings
- From: davef <davidfrick2003 at yahoo.com>
- Date: Wed, 29 Apr 2009 03:48:44 -0400 (EDT)
When I execute this in Mathematica 7:
Solve[3^(2 x) - 12 (3^x) + 27 == 0, x]
I get this:
Solve::ifun: Inverse functions are being used by Solve, so some solutions may not be found; use Reduce for complete solution information. >>
{{x->1},{x->2}}
1 amd 2 are proper solutions but is it possible to avoid the warning?
If I use Reduce:
Reduce[3^(2 x) - 12 (3^x) + 27 == 0, x]
I get a set of 1 and 2 added to some imaginary number terms that I don't quite understand.
I guess my question is: why would the use of inverse functions be so unreliable a solution as to necessitate a warning? And in the interest of clean output, can the warning be supressed other than by deleteing the cell?
Thanks