Re: General--Differential equation problem..

*To*: mathgroup at smc.vnet.net*Subject*: [mg66300] Re: General--Differential equation problem..*From*: "Steve Luttrell" <steve_usenet at _removemefirst_luttrell.org.uk>*Date*: Mon, 8 May 2006 00:46:51 -0400 (EDT)*References*: <e3jttb$94n$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

This works: DSolve[{Derivative[1][x][s] == Cos[z[s]], Derivative[1][y][s] == Sin[z[s]], Derivative[1][z][s] == 1/2}, {x, y, z}, s] Steve Luttrell West Malvern, UK <randomtalk at gmail.com> wrote in message news:e3jttb$94n$1 at smc.vnet.net... > hello, i was trying to solve a set of differential equations needed for a > school project.. However, i'm completely new to mathematica 5.0, and i > have downloaded trial, here is what i inputed into the software: > > In[2]:= > DSolve[{x'[s] == Cos[z], y'[s] == Sin[z], z'[s] == 1/r, r == 2}, {x, y, > z}, s] > > returns this error: DSolve::dvnoarg: The function z appears with no > arguments. > > Is there anything wrong with what i inputed? The differential equations > came from this website: http://fy.chalmers.se/LISEBERG/eng/loop_pe.html > > Link to the forum page for this post: > http://www.mathematica-users.org/webMathematica/wiki/wiki.jsp?pageName=Special:Forum_ViewTopic&pid=10212#p10212 > Posted through http://www.mathematica-users.org [[postId=10212]] > >