domesticbark
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Homework Statement
[itex] 2xy'+y^3e^(-2x)=2xy[/itex]
Homework Equations
[itex] dy/dx + P(x)y=Q(x)y^n[/itex]
[itex] v=y^(1-n)[/itex]
The Attempt at a Solution
[itex] dy/dx-y=-y^3e^(-2x)/2x[/itex]
[itex] P(x)=-1<br /> Q(x)=-e^(-2x)/2x[/itex]
[itex] n=3[/itex]
[itex] v=1/y^2[/itex]
[itex] dy/dx=dy/dv*dv/dx[/itex]
[itex] dy/dx=-1/2v^-(3/2)*dv/dx[/itex]
[itex] -1/2v^(-3/2)*dv/dx-v^(-1/2)=-v^(-3/2)e^(-2x)/2x[/itex]
[itex] dv/dx + 2v=e^(-2x)/x[/itex]
[itex] e^(\int P(x)\,dx)=e^(\int -1\,dx)=e^(-x)[/itex]
[itex] dv/dx*e^(-x)+2ve^(-x)=e^(-3x)/x[/itex]
This is supposed to look live reverse chain rule so I get [itex](e^(-x)*v)'=e^(-3x)/x[/itex]
but it doesn't look right and I have no idea how to do the integral required to then solve the rest of this problem.