On Sat, 2011-01-08 at 14:47 +0100, nijso beishuizen wrote:
> f:g(x)*exp(g(x))*diff(g(x),x);
> sol:integrate(f,x);
> ...
> However, integrate does not seem to be able to find this solution.
> antidiff by the way, is able to handle this problem correctly:
> antidiff(f,x,g(x));
> ...
> I am a bit puzzled. Why does integrate not handle this simple problem?
> Should integrate be able to handle this problem? Is there a way to get this
> solution without using antidiff?
> Or can I simply always use antidiff instead of integrate when I am only
> dealing with indefinite integrals?
Hi
look at the manual:
-- Function: integrate (<expr>, <x>)
Attempts to symbolically compute the integral of <expr> with
respect to <x>. `integrate (<expr>, <x>)' is an indefinite
integral.
-- Function: antidiff (<expr>, <x>, <u>(<x>))
Returns an antiderivative of <expr> with respect to <x>. The
expression <expr> may contain an unknown function <u> and its
derivatives.
Thus, the answers to your questions are: integrate is not supposed to
solve your problem. You should use antidiff and not integrate when expr
contains an unknown function and its derivatives, otherwise, you should
be able to use either integrate or antidiff.
Regards,
Jaime