System of DEs: Linear or Nonlinear? Competitive or Cooperative?

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Discussion Overview

The discussion revolves around the classification of a system of differential equations as linear or nonlinear, as well as the nature of the interactions between the variables, specifically whether they are competitive or cooperative. The scope includes theoretical analysis and conceptual clarification of the terms involved.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant suggests the system is nonlinear due to the presence of the xy terms, while another claims that Maple's classification of the first equation as linear is correct when considered in isolation.
  • There is a discussion about the nature of the system, with some participants asserting that the system as a whole is nonlinear because of the interaction terms.
  • Participants express uncertainty regarding the definitions of competitive and cooperative interactions, indicating a lack of clarity in available resources.

Areas of Agreement / Disagreement

Participants disagree on the classification of the system as linear or nonlinear, with competing views presented. The discussion on competitive versus cooperative interactions remains unresolved, with no consensus reached.

Contextual Notes

There is ambiguity regarding the definitions of competitive and cooperative interactions, and the classification of the system may depend on interpretations of linearity in the context of systems of equations versus individual equations.

mathlete
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[tex] \frac{dx}{dt} = -5x+2xy[/tex]
[tex] \frac{dy}{dt} = -4y+3xy[/tex]

Are these linear or nonlinear? I'm inclined to say non-linear but using maple it tells me it's linear ( odeadvisor(ode1, [linear]); returns [_linear] where ode1 is dx/dt).

Also, are they competitive or cooperative? I know it's not predator prey. I've graphed it and all solutions tend to 0, but I don't know what type that is (I can't find an explanation of cooperative/competitive anywhere on the internet)
 
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For the first question, they are definitely non-linear (xy terms). Maple is just wrong.

I can't answer the second question.
 
Apparently, you asked Maple whether the first equation is linear - which it is. With respect to the first equation alone, y = y(t) and it's clearly linear in the dependent variable x. The real question is whether the system of equations is linear - which it is not since the equations involve a product of the variables x and y.

For the second question you will have to resort to reading your textbook to know what the authors mean by cooperative vs. competitive.
 
OK thanks, I thought it had something to do with me just asking it about the one equation instead of the system.
 

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