RE: How to Integrate[Abs[x]]?

*To*: mathgroup at smc.vnet.net*Subject*: [mg91626] RE: [mg91624] How to Integrate[Abs[x]]?*From*: "Jaccard Florian" <Florian.Jaccard at he-arc.ch>*Date*: Sat, 30 Aug 2008 01:49:53 -0400 (EDT)*References*: <200808290825.EAA24127@smc.vnet.net>

Hello, It's because Mathematica considers x as a Complex number. So you can do it like this : In[35]:= Assuming[Element[x, Reals], Integrate[Abs[x], x]] Out[35]= Piecewise[{{-(x^2/2), x <= 0}}, x^2/2] Or like this : In[36]:= Integrate[Sqrt[x^2], x] Out[36]= (x*Sqrt[x^2])/2 Regards, F.Jaccard -----Message d'origine----- De : Thomas Dybdahl Ahle [mailto:lobais at gmail.com] Envoy=E9 : vendredi, 29. ao=FBt 2008 10:26 =C0 : mathgroup at smc.vnet.net Objet : [mg91624] How to Integrate[Abs[x]]? On my Ti calculater |x| is easily integrated to |x|*x/2, but when I type = Integrate[Abs[x],x] in mathematica, it seams like it can't find the = solution. Is there anything I'll have to do, to make mathematica find the = solution?

**References**:**How to Integrate[Abs[x]]?***From:*Thomas Dybdahl Ahle <lobais@gmail.com>