antispam@math.uni.wroc.pl schrieb:   
   >   
   > clicliclic@freenet.de wrote:   
   > >   
   > > clicliclic@freenet.de schrieb:   
   > > >   
   > > > [...] and then the "Preview" button hit, the following error message   
   > > > is returned after about five minutes:   
   > > >   
   > > > - - -   
   > > >   
   > > > Proxy Error   
   > > >   
   > > > The proxy server received an invalid response from an upstream server.   
   > > > The proxy server could not handle the request POST /FriCASIntegration.   
   > > >   
   > > > Reason: Error reading from remote server   
   > > >   
   > > > Apache/2.2.22 (Debian) Server at axiom-wiki.newsynthesis.org Port 80   
   > > >   
   > > > - - -   
   > > >   
   > >   
   > > Something is going on, or the server deteriorating further. Submitting   
   > > the same or even the trivial input:   
   > >   
   > > \begin{axiom}   
   > > integrate(x, x)   
   > > \end{axiom}   
   > >   
   > > I get a different and instantaneous OSError response today:   
   >   
   > Your orignal integral does not work because of a timeout:   
   > your integral is one of those that need _very_ long time.   
   > Web interface stops computation IIRC after 4 minutes.   
   >   
   > There seem to be resource leak in the web server, it needs   
   > restarting from time to time.  Befor restart you get errors   
   > trying to access any page.  ATM I am restarting it by hand...   
   >   
      
   Ah! Thanks for the explanation. The first error message gave no   
   indication that a timeout had intervened ...   
      
   Anyway, I won't submit this nasty integral again. The problem of this   
   pseudo-elliptic integrand seems to be that it involves the constant root   
   SQRT(a^2 + 1) in addition to the main radical SQRT((x - a)*(x^2 + 1)).   
   So not only nested radicals but also separate constant roots may slow   
   the FriCAS integrator down to a crawl, and in this case even with   
   SimplifyDenomsFlag set!   
      
   The elusive antiderivative is quite compact, however:   
      
   INT((x - SQRT(a^2 + 1) - a)/((x + SQRT(a^2 + 1) - a)   
   *SQRT((x - a)*(x^2 + 1))), x) =   
   - SQRT(2)*SQRT(SQRT(a^2 + 1) + a)*ATAN(SQRT(2)*SQRT(SQRT(a^2 + 1) - a)   
   *((x - a)/SQRT((x - a)*(x^2 + 1))))   
      
   Now left wondering how long _very_ long is in hours, say, or years ...   
      
   Martin.   
      
   --- SoupGate-Win32 v1.05   
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