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HallsofIvy
HallsofIvy is offline
#4
Jun5-11, 05:53 AM
Math
Emeritus
Sci Advisor
Thanks
PF Gold
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Integrating Factor, how do you get this?


As I said, they didn't "drop" mu, they solved for it!
If
[tex]\frac{du}{dx}= F(x)u[/tex]
then
[tex]\frac{du}{u}= F(x)dx[/tex]
and, integrating both sides,
[tex]ln(u)= \int F(x)dx[/tex]

Now take the exponential of both sides.