UH oh, integration of rational functions has a bug.
- To: mathgroup at smc.vnet.net
 - Subject: [mg41650] UH oh, integration of rational functions has a bug.
 - From: Richard Fateman <fateman at cs.berkeley.edu>
 - Date: Thu, 29 May 2003 08:14:40 -0400 (EDT)
 - Organization: University of California, Berkeley
 - Sender: owner-wri-mathgroup at wolfram.com
 
Mathematica 4.1
In[1]:=  1 + 5*x + a*x^2 + 10*x^3 + 5*x^4 + x^5
Integrate[1/%, x]
%1 /. a -> 10
Integrate[1/%, x]
%1 /. a -> c
Integrate[1/%, x]
InputForm[%]    ===>
RootSum[1 + 5*#1 + c*#1^2 + 10*#1^3 + 5*#1^4 + #1^5 & ,
   Log[x - #1]/(5 + 30*#1^2 + 20*#1^3 + 5*#1^4 +
      2*#1*Integrate`V[1][6]) & ]
WHAT is THIS ^^^^^^^^^^^^^^^ ??   and why did it not
appear in the identical problem where there was an "a"
instead of a "c" ??
It is somehow dependent on the sequence of commands.