Equilibrium solution limit to differential equation

Click For Summary

Discussion Overview

The discussion revolves around finding the limit of a solution to the differential equation dx/dt = x^3 - 4x as time approaches infinity, given an initial condition x(0) = 1. Participants explore equilibrium solutions and the stability of these solutions, as well as methods for solving the differential equation.

Discussion Character

  • Exploratory, Technical explanation, Homework-related, Mathematical reasoning

Main Points Raised

  • One participant seeks assistance in determining the limit of the solution as time approaches infinity after identifying equilibrium solutions.
  • Another participant confirms the equilibrium solutions as x = -2, 2, and 0, noting that only x = 0 is stable, but expresses uncertainty about the next steps.
  • Several participants suggest that the differential equation is separable and can be solved using Partial Fractions, with one mentioning that it can also be approached as a Bernoulli equation.
  • A later reply indicates that one participant has arrived at an answer, but does not specify what that answer is.

Areas of Agreement / Disagreement

Participants generally agree on the identification of equilibrium solutions, but there is no consensus on the next steps or the final limit of the solution as time approaches infinity.

Contextual Notes

Some assumptions regarding the stability of the equilibrium solutions and the methods for solving the differential equation remain unaddressed, and the discussion does not resolve the mathematical steps involved in finding the limit.

Vishak95
Messages
19
Reaction score
0
Can someone please help me with this one? I have found the equilibrium solutions,but I'm not sure what to do next.

Consider dx/dt = x^3 - 4x

Given a solution x(t) which satisfies the condition x(0) = 1, determine the limit(t -> infinity) of x(t).

Thanks!
 
Physics news on Phys.org
Well what did you get for your solution?
 
Prove It said:
Well what did you get for your solution?

I got the equilibrium solutions x = -2 , 2 and 0. Out out these only x = 0 is stable. Not sure where to go from here though...
 
I meant, what did you get for your solution to the DE? Hint: It's separable and can be solved using Partial Fractions.
 
Prove It said:
I meant, what did you get for your solution to the DE? Hint: It's separable and can be solved using Partial Fractions.

It's also Bernoulli, as an alternative.
 
Ok, thanks guys, I got the answer :)
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 52 ·
2
Replies
52
Views
8K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 16 ·
Replies
16
Views
3K