Integration using integrating factor

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Homework Help Overview

The discussion revolves around the integration of a first-order linear differential equation of the form dy/dx = 2y + 4x + 10, focusing on the use of an integrating factor to solve the equation.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the application of the integrating factor and the transformation of the equation into a form suitable for integration. There are attempts to clarify the differentiation of the product involving the integrating factor and the function y.

Discussion Status

Some participants have provided guidance on the integration process and the use of integration by parts. There is an ongoing exploration of how to handle the integral of the right side, with no explicit consensus reached on the next steps.

Contextual Notes

Participants express uncertainty about the integration of the right-hand side and the specifics of applying integration techniques, indicating a need for further clarification on these points.

xlalcciax
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Homework Statement


Integrate dy/dx=2y+4x+10


The Attempt at a Solution



dy/dx-2y=4x+10
Integrating factor = e^(-2)dx=e^-2x
multiply both sides by IF. (e^-2x)dy/dx-2y(e^-2x)=(e^-2x)(4x+10)
dy/dx(e^-2x y)=(e^-2x)(4x+10)
i don't know what to do next.
 
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xlalcciax said:

Homework Statement


Integrate dy/dx=2y+4x+10


The Attempt at a Solution



dy/dx-2y=4x+10
Integrating factor = e^(-2)dx=e^-2x
multiply both sides by IF. (e^-2x)dy/dx-2y(e^-2x)=(e^-2x)(4x+10)
dy/dx(e^-2x y)=(e^-2x)(4x+10)
i don't know what to do next.
The left side is actually d/dx(ye-2x), which is different from dy/dx(ye-2x).

The equation is d/dx(ye-2x) = (4x + 10)e-2x.
Integrate both sides with respect to x, which gives you
[tex]ye^{-2x} = \int (4x + 10)e^{-2x}dx[/tex]

Can you take it from here?
 
Mark44 said:
The left side is actually d/dx(ye-2x), which is different from dy/dx(ye-2x).

The equation is d/dx(ye-2x) = (4x + 10)e-2x.
Integrate both sides with respect to x, which gives you
[tex]ye^{-2x} = \int (4x + 10)e^{-2x}dx[/tex]

Can you take it from here?

i know that the left side is ye^-2x but i don't know how to integrate (4x + 10)e^{-2x}
 
Split the right-side integral into two integrals. For one of them, use integration by parts. The other one is pretty easy.
 

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