Re: Log Equation
- To: mathgroup at smc.vnet.net
- Subject: [mg44764] Re: Log Equation
- From: "Curt Fischer" <crf3 at po.cwru.edu>
- Date: Tue, 25 Nov 2003 00:45:32 -0500 (EST)
- References: <bps4gf$9uj$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Your equation has a real solution only for x less than about -0.2 or so. In
this range you could use FindRoot[].
In[1]:=
? FindRoot
In[2]:=
f[y_] :=
x /. FindRoot[y == \(1 - x\)\/Log[x], {x,
1 + $MachineEpsilon, \ 10\^6}]
In[3]:=
f[-2]
Out[3]=
3.51286
In[4]:=
f[-1]
Out[4]=
1.
In[5]:=
f[-7]
Out[5]=
22.9259
In[6]:=
\!\(f[\(-10\^4\)]\)
Out[6]=
116672.
--
Curt Fischer