(Newbie) More confusion with integral of absolute vals
- To: mathgroup at smc.vnet.net
- Subject: [mg9367] (Newbie) More confusion with integral of absolute vals
- From: "L. Dwynn Lafleur" <lafleur at usl.edu>
- Date: Sat, 1 Nov 1997 03:33:53 -0500
- Organization: U. of Southwestern Louisiana
- Sender: owner-wri-mathgroup at wolfram.com
Suppose I want to integrate the absolute value of x over the range a->b.
It's simple enough in Maple V Release 4:
> ii:=int(abs(x),x=a..b);
2 2
ii := 1/2 b signum(b) - 1/2 a signum(a)
> assume(0<a,a<b);
> ii;
2 2
1/2 b~ - 1/2 a~
where the tildes (~) indicate there are assumed properties for a and b.
If I try the same thing in Mathematica 3.01, I get
In[1]:= ii=Integrate[Abs[x],{x,a,b}] Out[1]= $Aborted
In other words, Mathematica cannot perform the integral and I must abort
the evaluation. Even if I try to place Assumptions in the Integrate
function, the integration is not performed. What am I missing here?
Can't the integration be performed as easily in Mathematica as it is in
Maple?
--
=========================================== L. Dwynn Lafleur
Professor of Physics
The University of Southwestern Louisiana Lafayette, Louisiana (USA)
lafleur at usl.edu
===========================================