How do you solve the differential equation dy/dx = xe^-x?

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Homework Statement



solve the diferential equation: dy/dx = xe^-x

Homework Equations





The Attempt at a Solution



dy/dx = xe^-x

dy = xe^-x dx
∫dy = ∫(xe^-x) dx

u = x and v ' = e^-x


That is all i really know to do I'm really confused and any help is appreciated.
 
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n.a.s.h said:

Homework Statement



solve the diferential equation: dy/dx = xe^-x

Homework Equations





The Attempt at a Solution



dy/dx = xe^-x

dy = xe^-x dx
∫dy = ∫(xe^-x) dx

u = x and v ' = e^-x


That is all i really know to do I'm really confused and any help is appreciated.

\frac{dy}{dx} = xe^{-x}

\int dy = \int xe^{-x}\;dx (*)

y= \cdots

the RHS of line (*) can be integrated by parts.

With u=x,\;u'=1,\;v'=e^{-x},\; v=-e^{-x}

Then \int v'u\;dx = uv - \int u'v\;dx

Once you've done that you've got your general solution (y=...) and don't forget the all important constant of integration.
 
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