First Order Linear Nonhomogenous Differential Equation

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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
 
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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