Re: Inverse Functions
- Subject: [mg3211] Re: [mg3184] Inverse Functions
- From: richard at seuss.math.wright.edu (Richard Mercer)
- Date: 17 Feb 1996 23:03:03 -0600
- Approved: usenet@wri.com
- Distribution: local
- Newsgroups: wri.mathgroup
- Organization: Wolfram Research, Inc.
- Sender: daemon at wri.com
> As a relatively inexperienced user of Mathematica, could > someone inform me how to get a closed-form expression--in > terms of elementary functions if possible--for the inverse > of the function > > f(x) = x^x > > Since the function is one-to-one over its domain, it does > have a mathematical inverse. x^x is not one-to-one on (0,inf). A graph over the interval (0,1) clearly fails the horizontal line test. Even on a restricted interval where it is one-to-one, there is no reason to believe one can write a closed-form expression (i.e. elementary function) for the inverse. I strongly suspect that is not possible in this case. Richard Mercer