Re: Vectors,Norms and assumptions
- To: mathgroup at smc.vnet.net
- Subject: [mg82764] Re: Vectors,Norms and assumptions
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Tue, 30 Oct 2007 05:43:39 -0500 (EST)
- Organization: Uni Leipzig
- References: <fg6rjo$e89$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
Hi, for Integrate[] there is a Option Assumptions->Element[{av1,av2},Reals] and for FullSimplify[]/Simplify[] there is a second argument for the assymptions and there a two functions Assuming[] and Refine[] to restrict the symbols to Reals or Integers .. and you can use the global variable $Assumptions to set the domains global. Regards Jens apsi wrote: > Hello, > I have a question in mathematica (actually 3). > > 1. Let v be v={av1,av2} , then Norm[v]=Sqrt[Abs[av1]^2 + Abs[av2]^2] > Q: How do indicate to mathematica that av1 and av2 belong to reals? > > 2. On a similar note, i have > n={an1,an2} > a={aa1,aa2} > (*an1,an2,aa1,aa2 are all reals*) > x=Norm[y(n-a)] >>> Sqrt[Abs[(-aa1 + an1) y]^2 + Abs[(-aa2 + an2) y]^2] > > Once again, how do i indicate that y ,an1,an2,aa1,aa2 are reals? > > Thank you for your time and help. > Rgds > Bveo > >