Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2003
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2003

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Finding solutions to differential eqns

  • To: mathgroup at smc.vnet.net
  • Subject: [mg40107] Re: Finding solutions to differential eqns
  • From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
  • Date: Fri, 21 Mar 2003 02:36:13 -0500 (EST)
  • Organization: Universitaet Leipzig
  • References: <b5bjbn$5qp$1@smc.vnet.net>
  • Reply-to: kuska at informatik.uni-leipzig.de
  • Sender: owner-wri-mathgroup at wolfram.com

Hi,

can you use Mathematica's syntax to give an equation ?

And

DSolve[(2 x[t]*t*(1 - t))*x'[t] == 1 + x[t]^2, x[t], t] // FullSimplify

return

{{x[t] -> -Sqrt[-1 + (E^(2*C[1])*t)/(-1 + t)]}, 
 {x[t] -> Sqrt[-1 + (E^(2*C[1])*t)/(-1 + t)]}}



In[]:=DSolve[x'[t] == (t/x[t])*Exp[x[t]/t] + x[t]/t, x[t], t] //
FullSimplify
Out[]={{x[t] -> -(t*(1 + ProductLog[(C[1] + Log[t])/E]))}}

In[]:=DSolve[x'[t] == (t - 4)*Exp[ 4 t] + t *x[t], x[t], t] //
FullSimplify
Out[]={{x[t] -> -E^(4*t) + E^(t^2/2)*C[1]}}

Regards
  Jens

David wrote:
> 
> Is there a method where you can get Mathematica to find general
> solutions for differential equations?  For example:
> 
> [2xt(1 + t)]dx/dt = 1 + x^2
> 
> dx/dt = (t/x)e^(-x/t) + x/t
> 
> and
> 
> dx/dt = (t - 4)e^4t + tx
> 
> I have access to version 4.0
> 
> Cheers,
> 
> David


  • Prev by Date: Re: Finding solutions to differential eqns
  • Next by Date: Re: simple question if/while loop
  • Previous by thread: Re: Finding solutions to differential eqns
  • Next by thread: RE: Finding solutions to differential eqns