3 problems.
Khiraly Kalman wrote:
> Hi!
The first problem is ...
> diff(integrate(cos(k*x)*cos(n*x),x));
should be...
diff(integrate(cos(k*x)*cos(n*x),x),x);
^^^^
>
> Why doesn't done the same resultat?:
> Theoretically diff(integrate(f(x)))=f(x)
Problem 2: This is actually NOT true if f has various strange things like
singularities. This is not the case here.
>
> But maxima doesn't.
Third problem: The two functions, call them A and B
ARE the same, which you can prove if
you compute
trigreduce(A - B).
Mathematics doesn't generally deal with the FORM
of the answer. Computer algebra systems generally
struggle with simplification, needed to show
that mathematical equality holds between two
forms that have different appearances.
RJF