On Feb 13, 2008 1:35 PM, reyssat <eric.reyssat at math.unicaen.fr> wrote:
> Does maxima know a way of combining sums which differ only by their
> bounds using additivity on bounds ?
>
> For instance, I don't know how to simplify (for n>0)
> s:sum(log(i),i,1,n+1)-sum(log(i),i,1,n);
> into
> log(n+1)
(%i1) s:sum(log(i),i,1,n+1)-sum(log(i),i,1,n);
(%o1) (sum(log(i),i,1,n+1))-sum(log(i),i,1,n)
(%i2) sumcontract(intosum(%));
(%o2) log(n+1)
> or simplify
> s2:sum(log(i),i,1,n)+sum(log(i),i,n+1,2*n);
> into
> sum(log(i),i,1,2*n)
This seems to work directly:
(%i3) s2:sum(log(i),i,1,n)+sum(log(i),i,n+1,2*n);
(%o3) sum(log(i),i,1,2*n)
HTH,
--
Andrej