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<A NAME=DILOG>

<TITLE>DILOG</TITLE></A>
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<B>DILOG</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>dilog</em> operator is known to the differentiation and integration 
operators, but has numeric value attached only at <em>dilog(0)</em>. Dilog is 
defined by 
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dilog(x) = -int(log(x),x)/(x-1) 
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examples: </H3>
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df(dilog(x**2),x); 

           2
    2*LOG(X )*X
  - ------------
       2
      X   - 1



int(dilog(x),x); 

  DILOG(X)*X - DILOG(X) + LOG(X)*X - X 



dilog(0); 

    2
  PI
  ----
   6

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