Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1999
*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 1999

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

Search the Archive

Some problems with DSolve and NDSolve

  • To: mathgroup at smc.vnet.net
  • Subject: [mg19745] Some problems with DSolve and NDSolve
  • From: "Chee Lim Cheung" <cheelc at mbox2.singnet.com.sg>
  • Date: Wed, 15 Sep 1999 03:53:01 -0400
  • Sender: owner-wri-mathgroup at wolfram.com

Hi MathGroupers,

I was somewhat surprised that DSolve is unable to solve the following
relatively innocuous system of 1st-order ODEs:

DSolve[{2 i1[t] + 2 (i1'[t] - i2'[t]) == 80 t E^(-2t), 4 i2[t] + 2 (i2'[t]
- i1'[t]) == 0, i1[0] == 0, i2[0] == 0}, {i1[t],i2[t]}, t]

The normally reliable NDSolve also falls down on the following:

NDSolve[{2 i1[t] + 2(i1'[t] - i2'[t]) == 80 t E^(-2t), 4 i2[t] + 2(i2'[t] -
i1'[t]) == 0, i1[0] == 0, i2[0] == 0}, {i1[t], i2[t]}, {t, 0, 1}]

What is wrong?

Thanks
Chee


  • Prev by Date: RE: RGB color cube & HLS color cone
  • Next by Date: simple Simplify[] question
  • Previous by thread: Re: Re: RealTime3D in v4.0
  • Next by thread: Re: Some problems with DSolve and NDSolve