Differential Equation isolation

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Lanza52
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Solve the differential equation:

[tex]\frac{dy}{dx}-\frac{y}{x}=3x^{2}[/tex]

Where y(1)=3

Can't figure out how to isolate each side. Played with it forever to no success. Any tips?
 
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...whenever you have a function of the form:

[tex]\frac{dy}{dx}+Py=Q[/tex] where both P and Q are functions of x..
you multiply throughout by [itex]e^{\int P dx}[/itex] and then integrate both sides with respect to x...

HINT: When you multiply throughout by [itex]e^{\int P dx}[/itex] and then integrate both sides with respect to x

The left hand side becomes [itex]ye^{\int P dx}[/tex][/itex]
 
If you want to use separation of variables you can solve the complimentary equation and use variation of parameters.