First Order Linear Nonhomogenous Differential Equation

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IBY
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A question, if you have a nonhomogenous first order differential equation, can it be solved by using the usual nonhomogenous way, with the arbitrary constants, instead of using the integrating factor?
 
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You can use variation of parameters or method of superposition
 
The question did NOT state that the equation was linear and both "variation of parameters" and the "method of superposition" require that the equation be linear.
 
So, let's take the following:
[tex]Ay'+By=C[/tex]

I know its solution is: [tex]\frac{C}{B}(1-e^{-t\frac{B}{A}})[/tex]

For the homogenous part:
[tex]Ay'+By=0[/tex]
Characteristic equation is:
[tex]Ak+B=0[/tex]
[tex]k=-\frac{B}{A}[/tex]

So the solution for the homogenous part is:
[tex]y=e^{-t\frac{B}{A}}[/tex]

Now, from what I have read about variation of parameters, there is a function v such that:
[tex]Y=vy[/tex]
[tex]Y'=v'y+vy'[/tex]

So, would that be:
[tex]vBe^{-t\frac{B}{A}}=Y[/tex]
[tex]v'Be^{-t\frac{B}{A}}-v\frac{B^2}{A}e^{-t\frac{B}{A}}=Y'[/tex]

Err... Correct?
 
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