Re: log expression not simplified

*To*: mathgroup at smc.vnet.net*Subject*: [mg115688] Re: log expression not simplified*From*: Michael Weyrauch <michael.weyrauch at gmx.de>*Date*: Tue, 18 Jan 2011 05:51:27 -0500 (EST)*References*: <ih16cv$jke$1@smc.vnet.net>

The following works and produces -1 as a result Simplify[FullSimplify[ComplexExpand[Log[a/b]/Log[b/a]]], Assumptions -> {a > 0, b > 0}] Its probably so complicated because of the cut of Log[] on the real axis (in the complex plane). Michael Am 17.1.2011 11:41, schrieb Praeceptor: > Sorry, can anybody help me understand why > > Simplify[Log[a/b]/Log[b/a], Assumptions -> {a> 0, b> a}] > > doesn't reduce to -1 ?? > Thanks (it's for a simple Carnot cycle calculation...)! >