Differential equations separation of variables

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The discussion centers on the separation of variables method for solving the differential equation xdv/dx=(1-4v^2)/3v. A participant expresses uncertainty about their separation of variables approach, which is confirmed to be mostly correct but with a minor mistake regarding the placement of dx. The correct form should be xdv = (1-4v^2)/3v dx, leading to dx/x = 3v/(1-4v^2) dv. The integration process is straightforward from this point, and applying initial conditions is recommended for a complete solution. The conversation emphasizes the importance of proper variable separation in differential equations.
EP
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xdv/dx=(1-4v^2)/3v

I used separation of variables to get

x/dx=(1-4v^2)/3v dv

I'm not sure if that's even right.

But if it is right, how do I integrate that?
 
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Your Separation of variables looks good, now a simple substitution finishes the job.
 
EP said:
xdv/dx=(1-4v^2)/3v

I used separation of variables to get

x/dx=(1-4v^2)/3v dv

I'm not sure if that's even right.

But if it is right, how do I integrate that?
You made a slight mistake with the variable seperation--- you can't have dx in the denominator! (Atleast, I've learned not to do it)
You should have done:
xdv = (1-4v^2)/3v dx
dx/x = 3v/(1-4v^2) dv
Integration from there is pretty simple... apply your initial conditions. :)
 
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