Wronskian Second Solution/Differential Equations

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Homework Statement



Given that Φ2 = Φ1 * ∫ e^(-∫a(x)dx)) / (Φ1)^2 dx

and Φ1 = cos(ln(x)), a = 1/x, solve for Φ2.

Homework Equations



The Attempt at a Solution



Φ2 = cos(ln(x)) * ∫ e^(-∫1/x dx)) / cos^(2)(ln(x)) dx

= cos(ln(x)) * ∫ e^(-ln(x)) / cos^(2)(ln(x)) dx

= cos(ln(x)) * - ∫ x / cos^(2)(ln(x)) dx

My problem begins here with trying to solve for that integral. I don't have the slightest idea where to begin, except maybe integration by parts.
 
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I believe you have expanded your brackets in the exponential wrong e^{-ln(x)} does not equal -x but rather e^{ln(x^{-1})} which is of course \frac{1}{x} in which case a simple u substitution will work
 
djeitnstine said:
I believe you have expanded your brackets in the exponential wrong e^{-ln(x)} does not equal -x but rather e^{ln(x^{-1})} which is of course \frac{1}{x} in which case a simple u substitution will work

Thanks for catching that mistake.
 
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