Wronskian Second Solution/Differential Equations

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In summary, the problem involves solving for Φ2, given that Φ2 = Φ1 * ∫ e^(-∫a(x)dx)) / (Φ1)^2 dx, and Φ1 = cos(ln(x)), a = 1/x. The attempt at a solution involves expanding the brackets in the exponential, e^{-ln(x)} becomes e^{ln(x^{-1})}, and using a simple u substitution to solve the integral.
  • #1
tracedinair
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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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  • #2
I believe you have expanded your brackets in the exponential wrong [tex]e^{-ln(x)}[/tex] does not equal [tex]-x[/tex] but rather [tex]e^{ln(x^{-1})}[/tex] which is of course [tex]\frac{1}{x}[/tex] in which case a simple u substitution will work
 
  • #3
djeitnstine said:
I believe you have expanded your brackets in the exponential wrong [tex]e^{-ln(x)}[/tex] does not equal [tex]-x[/tex] but rather [tex]e^{ln(x^{-1})}[/tex] which is of course [tex]\frac{1}{x}[/tex] in which case a simple u substitution will work

Thanks for catching that mistake.
 

What is the Wronskian Second Solution?

The Wronskian Second Solution, also known as the method of variation of parameters, is a technique used to find a second linearly independent solution to a non-homogeneous linear differential equation. This method is often used when the first solution to the equation is known.

How is the Wronskian Second Solution used in differential equations?

The Wronskian Second Solution is used to find a second solution to a non-homogeneous linear differential equation. This is important because it allows us to find the general solution to the equation, which is a combination of the two linearly independent solutions.

What is the difference between the Wronskian Second Solution and the Wronskian First Solution?

The Wronskian First Solution is used to find a single solution to a homogeneous linear differential equation, while the Wronskian Second Solution is used to find a second solution to a non-homogeneous linear differential equation. Additionally, the Wronskian Second Solution requires the first solution to be known, while the Wronskian First Solution does not.

What is the process for using the Wronskian Second Solution?

The process for using the Wronskian Second Solution involves finding the Wronskian of the two linearly independent solutions to the differential equation, and then using that to solve for the coefficients of the second solution. This method can be complex and involves finding integrals and solving systems of equations.

When is the Wronskian Second Solution applicable?

The Wronskian Second Solution is applicable when the first solution to the differential equation is known and when the equation is non-homogeneous. This method is not applicable for homogeneous equations, as the Wronskian will always be zero in that case.

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