Re: algebraic manipulation

*To*: mathgroup at smc.vnet.net*Subject*: [mg22376] Re: algebraic manipulation*From*: "Allan Hayes" <hay at haystack.demon.co.uk>*Date*: Sat, 26 Feb 2000 22:05:03 -0500 (EST)*References*: <897eqv$5u3@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Peter, Mathematica 4.0x gives k r Cos[k r]/(Sqrt[k] r^3) (Sqrt[k]*Cos[k*r])/r^2 With Mathematica 3.x you might like to try PowerExpand Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 "Peter Jay Salzman" <covenant at dirac.org> wrote in message news:897eqv$5u3 at smc.vnet.net... > sorry to ask such a simple question... > > i have a very long espression of the form > > A[k, r]( B[k,r] + C[k,r] + blah blah blah) > ------------------------------------------ > D[k, r] > > it took me awhile to figure out how to decompose this (i was trying to use > Apart. instead, ExpandAll seemed to do the trick). > > but i'm still seeing terms that look like: > > k r cos(k r) > ------------- > \sqrt{k} r^{3} > > no amount of coaxing seems to make Mathematica want to reduce this to: > > \sqrt{k} \cos(k r) > ------------------ > r^{2} > > FullSimplify just undoes ExpandAll and puts everything over a common > denominator. i want separate terms which are fully reduced. > > how can i have Mathematica aggresively reduce these individual terms? > > thanks! > pete > >