Euler-Lagrange Equation for a Stationary Action

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SUMMARY

The discussion centers on the application of the Euler-Lagrange equation for the functional L(y, y', x) = y² + (y')². The user initially struggles with deriving the correct equation using the differential form of the Euler-Lagrange equations for stationary action. After some confusion regarding the treatment of dynamical variables, the user realizes that these variables should be treated as functions rather than mere variables, leading to a resolution of their problem.

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Homework Statement



If L(y, y', x) = y^{2} + y'^{2} then find the appropriate Euler Lagrange Equation. I have absolutely no idea how to solve this. I used the differential form of the Euler Lagrange equations for a stationary action but the answer i got was nothing like the answer in the book so could anyone show me how to find the equation using the differential form?
 
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This is perfectly straightforward. Can you show us what you got and what the books answer is?
 
Dick said:
This is perfectly straightforward. Can you show us what you got and what the books answer is?

Never mind I got it I keep forgetting the dynamical variables are actually functions and I keep treating them like variables in the equation. Stupid mistakes on my part. Sorry.
 
Last edited:

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