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Topic: Integration by substitution.
Replies: 5   Last Post: Dec 17, 2012 2:53 PM

 Messages: [ Previous | Next ]
 Red Star Posts: 136 Registered: 6/28/08
Re: Integration by substitution.
Posted: Dec 15, 2012 4:10 AM

I'm sorry, I try to better explain my point.
Let's suppose this is a ODEs I want to solve.
http://www.mathworks.it/help/matlab/ref/eqn1311792846.png

y' are derivatives w.r.t the time.
I could use a Runge-Kutta method to solve them from t0 a the final time (please, see http://www.mathworks.it/it/help/matlab/ref/ode45.html). Well done.

Now let's suppose I would integrate my problem in auxiliary variable, let' say E. It is only theoretically.
(e.g. E = t^2 or E = sin(t),...). I am able to expres t0 e in tf in terms of E.
How can I solve my ODE now? It is sufficient to multiply y' with dt/dE and use my Runge Kutta?

Thanks for your support

Date Subject Author
12/14/12 Red Star
12/14/12 William Elliot
12/15/12 Red Star
12/17/12 Torsten Hennig
12/16/12 Ken.Pledger@vuw.ac.nz
12/17/12 Red Star