Laplace DE separation of variables

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Homework Help Overview

The problem involves finding a nontrivial solution to a differential equation of the form tx'' + (t-2)x' + x = 0, with the initial condition x(0) = 0. The original poster has reached an intermediate equation in the Laplace transform domain and is seeking to separate variables to derive a specific solution.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to separate variables from the equation (s+1)X'(s) + 4X(s) = 0 but is uncertain about how to proceed after integrating, particularly with the presence of natural logarithms.

Discussion Status

Some participants have offered guidance regarding the manipulation of natural logarithms, suggesting that raising both sides to the power of e may help resolve the issue. However, the original poster later expressed uncertainty about this approach.

Contextual Notes

The original poster has been working on the problem for an extended period and is facing challenges with the integration process and the resulting expressions. There may be constraints related to the homework guidelines that influence the discussion.

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Homework Statement


I'm supposed to find a nontrivial solution to tx'' + (t-2)x' + x = 0, x(0) = 0. You don't really need to know that but just in case.

I got to this point:
(s+1)X'(s) + 4X(s) = 0

Now I need to separate variables to find a solution but I've been working on this for two days and can't figure out how to get to the correct solution, which is:
X(s) = C/(s+1)^4

So my question is, how do I go from the first equation to the second using separation of variables?

Homework Equations





The Attempt at a Solution


I've been trying for two days now.. with X(s) = X and X'(s) = dX/ds, I separated all X's and dX's and the same with s and ds.. then when I took the integral of both sides, I get natural logs since I'm doing the integral of 1/x and 1/(s+1) ... I don't know where to go with natural logs, since that's not the answer.

Any help would be appreciated, thanks!
 
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as you have natural log on both sides, you should be able to remove it by raising both sides to the power of e...
 
Ah, right! That solves my entire dilemma! *phew* thanks so much for pointing that out ;)
 
scratch that
 

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