> Try logcontract(log(a)-log(b)) --> log(a/b)
Unfortunately, logcontract uses (why?) ratsimp, so you get such messes as
logcontract ( log((x+1)^5) - log(x) ) =>
log((x^4+4*x^3+6*x^2+4*x+1)/x)
Of course, you can simplify again using scanmap(factor,%,bottomup),
but in more complicated cases this doesn't help, e.g.
logcontract ( log((x+1)^5 + 1) - log(x) )
If you look at Hugemann's original problem, what it is really looking
for is a fancier version of factorsum, which with some massaging gets
the expression down to:
2*(v0-a*t)*((v0-a*t)*log((v0-a*t)/v0)+a*t)+a^2*t^2
or
2*(v0-a*t)^2*log((v0-a*t)/v0)+a*t*(2*v0-a*t)
I am cleaning up the solution, and will probably send it out tomorrow.
-s