# Wronskian

• January 13th 2011, 03:30 PM
Mathsnewbie
Wronskian
Hey guys I understand most of how to do a Wronskian but I don't understand where you get an integrating factor. Going to upload the example sheet if someone could explain the steps I've circled I'd be much obliged.

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• January 13th 2011, 05:02 PM
dwsmith
When you have a DE in the form, $y'+p(x)y=f(x)$, the integrating factor is $\displaystyle\exp{\left(\int p(x)dx\right)}$

$\displaystyle\int\frac{d}{dx}\left[\exp{\left(\int p(x)dx\right)}y\right]dx=\int\left[\exp{\left(\int p(x)dx\right)}f(x)\right]dx$