Linearity of ODE: (1 x^2) dy/dx + y = 0

  • Context: Undergrad 
  • Thread starter Thread starter RiceKernel
  • Start date Start date
  • Tags Tags
    Linearity
Click For Summary

Discussion Overview

The discussion revolves around the concept of linearity in ordinary differential equations (ODEs), specifically examining the equation (1 x^2) dy/dx + y = 0. Participants explore the criteria that determine whether an ODE is linear, considering both the structure of the equation and the implications of the dependent variable and its derivatives.

Discussion Character

  • Conceptual clarification, Debate/contested

Main Points Raised

  • One participant, GT, expresses confusion about the linearity of the given ODE, suggesting it may be linear because the dependent variable and its derivatives are not multiplied together, but questions arise due to the presence of the x^2 term.
  • Another participant proposes a definition of linearity, stating that an ODE is linear if the sum of any two solutions is also a solution, and challenges GT to demonstrate this property with the given equation.
  • Some participants express frustration with the request for a definitive yes or no answer, indicating a desire for more straightforward responses rather than detailed explanations.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the linearity of the ODE. There are differing views on how to approach the question, with some seeking a simple answer and others advocating for a more thorough exploration of the concept.

Contextual Notes

There is a lack of clarity on the definitions and criteria being applied to assess linearity, as well as differing expectations regarding the depth of discussion appropriate for the forum.

RiceKernel
Messages
17
Reaction score
0
Hi , I have no problem to solve but just a bit of confusion on what determines the linearity of an ODE.

Let's say the equation is (1 x^2) dy/dx + y = 0

Is it linear ? I would incline to say yes because the dependent variable and its derivatives are not in a product with each other but the square on the x makes me doubt the linearity or does it not matter at all? If it was (1-y^2), it wouldn't be linear because the coefficient has the dependent variable in it.

Thanks ,
GT
 
Physics news on Phys.org
An ODE is linear if the sum of any two solutions to it is also a solution.

Suppose we have two functions, ##y_{1}## and ##y_{2}##, and they both satisfy the ODE:

##(1-x^{2})\frac{dy_{1}}{dx} + y_{1}=0##
##(1-x^{2})\frac{dy_{2}}{dx} + y_{2}=0##

Can you show that ##y_{1}+y_{2}## also satisfies the ODE? If you can, then the eq is linear.
 
Not helpful at all . Just had to say yes or no .
 
give a man a fish...
 
RiceKernel said:
Not helpful at all . Just had to say yes or no .
Do the work and you'll get your answer. This isn't a forum for babies, please read the rules.
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K