x does not need declaration, it is declared automatically
Robert
On 18 zář, 09:08, sps <debernasave...@libero.it> wrote:
> On 17 Set, 23:03, Yann <yannlaiglecha...@gmail.com> wrote:
>
>
>
> > If I try this, here is what I get:
>
> > sage: var('a')
> > a
> > sage: integral(cos(2*x)/(x^2+a^2),x,-Infinity,+Infinity)
> > ERROR: An unexpected error occurred while tokenizing input
> > ...
> > TypeError: Computation failed since Maxima requested additional
> > constraints (try the command 'assume(a>0)' before integral or limit
> > evaluation, for example):
> > Is a positive, negative, or zero?
>
> > Ok, let's do this
>
> > sage: assume(a>0)
> > sage: integral(cos(2*x)/(x^2+a^2),x,-Infinity,+Infinity)
> > pi*e^(-2*a)/a
>
> > Is it what you expect?
>
> Yes, it is!
>
> But I don't declare also 'x' as variable?
> I digited:
> x,a=var('x,a')
> Is it not correct?
--
To post to this group, send email to sage-support@googlegroups.com
To unsubscribe from this group, send email to
sage-support+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/sage-support
URL: http://www.sagemath.org
