MathGroup Archive 2002

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

Search the Archive

silly newbie questions

  • To: mathgroup at smc.vnet.net
  • Subject: [mg34385] silly newbie questions
  • From: heimantj at celera.com (theiman)
  • Date: Fri, 17 May 2002 06:31:22 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Hi,

I have two questions:

(1)  I have an equation:

          eqn = A'[t] = S - (ln(2)/hl)*A[t]

and I am trying to find the time at which the discontinuity occurs (t1
and t2) and I have sampled at time t.  The constraints for the system
are:
 
 S(t)=S if t1<t<t2
 S(t)=0 otherwise

The question is: How do I use these constraints with Dsolve?

(2) After I find the solution to the equation in question 1 I would
like to take the laplace transform of the equation (and since it is a
step function I need to use the heaviside (formula/equation?)) and
solve the result.  Any ideas on how to do this?

I would really appreciate any help or suggestions!!!! 

Thankyou!!

Sincerely,

Tom


  • Prev by Date: Re: solving vector equations in mathematica
  • Next by Date: Fwd: Re: HTMLSave and Heading
  • Previous by thread: Notations / syntax extension
  • Next by thread: RE: silly newbie questions