Re: Simple question about inverse of a function

*To*: mathgroup at smc.vnet.net*Subject*: [mg122525] Re: Simple question about inverse of a function*From*: Bob Hanlon <hanlonr357 at gmail.com>*Date*: Mon, 31 Oct 2011 06:49:40 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <201110300922.EAA15359@smc.vnet.net>

f[t_] := (1 - t)^theta InverseFunction[f][x] // Quiet 1 - x^(1/theta) Plot3D[InverseFunction[f][x], {x, 0, 1}, {theta, 0, 5}] // Quiet Bob Hanlon On Sun, Oct 30, 2011 at 5:22 AM, Mikael <mikaen.anderson.1969 at gmail.com> wrote: > I have a simple question on how to calculate the inverse of a a function. This is the function I define: > > f[t_] := (1 - t)^theta > > To calculate the inverse I write: > > Assuming[t >= 0 && t <= 1 && theta >= 1 && theta < Infinity, { InverseFunction[f[t]]}] > > but the answer I get is > > {InverseFunction[(1 - t)^theta]}. > > Now I know I can do this: > > In[11]:= Solve[f[g[x]]==x,g[x]] > Out[11]= {{g[x]->1-x^(1/theta)}} > > but I wonder what is the correct way of specifying assumptions on t and theta to make the InverseFunction work. Thanks. >

**References**:**Simple question about inverse of a function***From:*Mikael <mikaen.anderson.1969@gmail.com>