Maxima doesn't support anything like assume(a>1 or a<-2) directly.
You can, however, use:
assume(abs(x+1/2)>3/2)
assume((x+1/2)^2>9/4)
but Maxima can only make limited inferences from this. For example:
assume(abs(x)>1,y^2>1)
is(abs(x)>1) => true <<< OK
is(x^2>1) => unknown <<< no inference
is(abs(y)>1) => unknown <<< no inference
is(y^2>1) => true <<< OK
Maybe that is enough for your application, especially if you assume *both*
forms.
On the other hand, Barton Willis's Fourier elimination method in
to_poly_solve <http://maxima.sourceforge.net/docs/manual/de/maxima_75.html>can
do useful things with Boolean expressions of inequalities.
-s
On Mon, Jan 7, 2013 at 3:31 PM, Ren? K?lin <renekaelin at gmx.ch> wrote:
> Dear list
>
> Is it possible to use "or" with assume? Something like assume(x>1 or x<-2)?
>
> Thank you.
>
>
> _______________________________________________
> Maxima mailing list
> Maxima at math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima
>