Axel Vogt schrieb:   
   >   
   > Do not mind, Maple has a bug:   
   >   
   > expr:= log(1 + 2*a*cos(2*x) + a^2)*sin(x)^2:   
   > R:=Int(expr,x=0..Pi/2);        # task   
   > r:= value(%) assuming 1 < a^2; # result   
   >   
   > Now check:   
   >   
   > R=r; eval(%, a=3/2);   
   > evalf(%);                      # using 15 decimals   
   >                                                                -13   
   >    0.113304326861497 = -1.17809724509622 - 0.180900313639568 10    I   
   >   
   > Ignoring the spurious imaginary it has false sign, at least.   
      
   And Nasser's (unsimplified) result for a = 3/2 on Derive 6.10 gives the   
   same -3*pi/8 = -1.17809724509617 (exact and to 15 decimals).   
      
   This confirms my initial diagnosis. I had overlooked that the arc sine   
   in Maple's result is imaginary for a < 0 and complex for a > 0 (at least   
   when Derive's definition is used).   
      
   Martin.   
      
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