From: nma@12000.org   
      
   Rubi 4.14.6  can integrate   
      
           (x Exp[x])/(1 - Exp[x])     (1)   
      
   but not   
      
           (x Exp[x])/(1 - Exp[-x])    (2)   
      
   I was just wondering why that is. Could not figure what changes   
   in rules needed. Since the result are very similar (in terms   
   of PolyLog, which Rubi supprts). For example, for (1) it   
   gives   
      
   In[59]:= rubi = Int[(x Exp[x])/(1 - Exp[x]), x]   
   Out[59]= -x Log[1 - E^x] - PolyLog[2, E^x]   
      
   But for (2) it does not evaluate it. Mathematica gives for (2)   
      
   In[60]:= mma = Integrate[(x Exp[x])/(1 - Exp[-x]), x]   
   Out[60]= E^x (-1 + x) + x Log[1 - E^x] + PolyLog[2, E^x]   
      
   thanks   
   --Nasser   
      
   --- SoupGate-Win32 v1.05   
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