Re: How do I force Log[Exp[x]]=x
- To: mathgroup at smc.vnet.net
- Subject: [mg22033] Re: How do I force Log[Exp[x]]=x
- From: Harald Giese <giese at ifm.uni-hamburg.de>
- Date: Fri, 11 Feb 2000 02:38:15 -0500 (EST)
- Organization: Institut fuer Meereskunde, Universitaet Hamburg
- References: <87tp95$5ia@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Bart Killam wrote: > > For real x, Log[Exp[x]]=x. For general complex x > Mathematical leaves this expression unevaluated. I > have tried Log[Exp[x/;Im[x]=0]], but this give a result > of 0. > > How do I tell Mathematica that I want the expression > simplied for real x ? Thanks for any help. Hi, This does the job: Simplify[Log[Exp[x]], x \[Element] Reals] /Harald -- Harald Giese Email: giese at dkrz.de Phone: +49 (0)40 42838 5796; Fax: +49 (0)40 5605724 Institut fuer Meereskunde der Universitaet Hamburg (Institute of Oceanography of the University of Hamburg) Troplowitzstrasse 7, D-22529 Hamburg