What are the solutions and domains for Homogenous Linear Equations (Wave)?

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Discussion Overview

The discussion revolves around the solutions and domains of homogeneous linear equations, specifically in the context of wave equations. Participants explore methods for verifying solutions and the implications of different intervals on the existence of these solutions.

Discussion Character

  • Homework-related, Mathematical reasoning

Main Points Raised

  • One participant seeks help with a problem related to homogeneous linear equations in preparation for a test.
  • Another participant suggests taking derivatives of a proposed solution and substituting them into the ordinary differential equation (ODE) to verify if it holds true.
  • A participant questions whether the interval of the solution affects its validity, specifically asking about the implications of a different interval (0 to 1).
  • Another participant clarifies that the solutions are defined for all real $x$, indicating that the ODE or solution will specify the domain of validity.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the implications of different intervals for the solutions, as one participant raises a question about it while another asserts that the solutions are valid for all real $x$.

Contextual Notes

The discussion includes assumptions about the definitions of the solutions and the ODE, as well as the implications of the interval on the existence of the solutions, which remain unresolved.

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i have a test on friday that I am studying for so i was working through some problems in my textbook. i came across this question and I am stuck on what to do. can anyone help me out?
thanks
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What you can do here is take the first and second derivatives (with respect to $x$) of the solutions given and substitute them into the given ODE and see if an identity results. For example, let's do $y_1$:

$$y_1=e^{2x}$$

And so we find:

$$y_1'=2e^{2x}$$

$$y_1''=4e^{2x}$$

And then substituting these into the ODE, we find:

$$4e^{2x}-7\cdot2e^{2x}+10e^{2x}=0$$

$$0=0$$

Thus, we know $y_1$ is a solution of (A). Try the other two...:D
 
I understand now ^^ but what if it were on a different interval from like 0 to 1 instead. Would that make a difference or does it mean that the function only exists on this interval?
 
As given, the solutions are defined for all real $x$. The ODE and/or solution will tell you where the solution is defined, either explicitly, or implied. :D
 

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