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Differential Eqn Question

doc_17 · 2015-08-23 13:08:37

Hi folks, just looking for a wee bit of help with a first order differential equation. Can I use the separation of variables with this? dy/dx - 3y/(x+1) = (x+1)^4

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23-08-2015 2:08pm

#1

doc_17

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Hi folks, just looking for a wee bit of help with a first order differential equation. Can I use the separation of variables with this?

dy/dx - 3y/(x+1) = (x+1)^4

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#2 28-08-2015 1:05am
ride-the-spiral

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I don't think this is seperable. If you check
http://tutorial.math.lamar.edu/Classes/DE/Separable.aspx
it explains that to be seperable "all of the y's must multiply the derivative."

This is an inhomogeneous ODE, so the solution will be the sum of solution to the homogeneous case and any solution to the inhomogeneous case. The homogeneous case is when the RHS is zero.

dy/dx - 3y/(x+1) = 0

Now this *can* be solved using seperation of variables. The harder part is inhomogeneous solution. You'll have to find the integrating factor to solve it.

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#3 28-08-2015 5:19am
gctest50

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found dat might be useful to someone in the future looking at this thread

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