Solving ODE via Separation Method: Need Assistance

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Discussion Overview

The discussion centers around solving the ordinary differential equation (ODE) dy/dx = e^(x+y) using the separation of variables method. Participants seek assistance in finding a general solution and addressing challenges encountered during the process.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant expresses difficulty in applying the natural logarithm to -e^(-y) and seeks help in solving the ODE.
  • Another participant suggests moving the minus sign in front of e^(-y) to the other side of the equation before applying the logarithm.
  • A different participant points out that a constant of integration has been overlooked, proposing a solution form y = -ln(C - e^x), which is valid under certain conditions (C > e^x or x < ln(C)).
  • A repeated request for assistance reiterates the initial problem and the approach of separating variables, followed by an attempt to integrate both sides.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the solution method or the treatment of the constant of integration, indicating that multiple approaches and viewpoints remain in the discussion.

Contextual Notes

Some assumptions regarding the integration process and the handling of the constant of integration are not fully explored, and the implications of the proposed solution forms are not resolved.

Mugged
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Can anyone help me solve this ODE:
..in other words, find a general solution?

dy/dx = e^(x+y)

I use a separation method, but i can't take the natural log of -e^(-y).
So, help?
 
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Perhaps you can move the minus in front of e-y to the other side of your equation before you apply log.
 
Looks to me like you have forgotten the constant of integration. You should get something like y= -ln(C- e^x) which exists only for C&gt; e^x or x&lt; ln(C)
 
Mugged said:
Can anyone help me solve this ODE:
..in other words, find a general solution?

dy/dx = e^(x+y)

I use a separation method, but i can't take the natural log of -e^(-y).
So, help?

e^(x+y) = e^x * e*y
e^(-y) dy = e^x dx
integrate both sides
 

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