Re: [Axiom-developer] problems with integrate

[Waldek Hebisch]

Tim Daly wrote:
> 
> Question from Thomas Baruchel
> 
> integrate((16*x^14-125*x^10+150*x^6+375*x^2)/(256*x^16+480*x^12+1025*x^8+750*x^4
>  +625),x=0..1)
> 
>           5
>     (1)  --
>          77
>                    Type: Union(f1: OrderedCompletion(Expression(Integer)),...)
> (2) -> 
> integrate((16*x^14-125*x^10+150*x^6+375*x^2)/(256*x^16+480*x^12+1025*x^8+750*x^4
>  +625),x)
> 
>                 7      3
>               5x  + 35x
>     (2)  -------------------
>              8       4
>          176x  + 165x  + 275
>                                           Type: Union(Expression(Integer),...)
> (3) -> D( (5*x^7+35*x^3)/(176*x^8+165*x^4+275) ,x)
> 
>                    14        10       6        2
>               - 80x   - 2575x   + 350x  + 2625x
>     (3)  -------------------------------------------
>               16        12         8        4
>          2816x   + 5280x   + 11275x  + 8250x  + 6875
>                                            Type: Fraction(Polynomial(Integer))


AFAICS logarithmic terms got lost.  FriCAS on the same input
produces ugly, long answer containing several logarithmic
terms.  The above agrees with rational part of FriCAS answer.
Old code contained a bug which sometimes caused such effect.

-- 
                              Waldek Hebisch
address@hidden