What do you do when time is present in Lagragian Equation?

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I set up a Lagragian equation that involves time t. What do I do? I only know how to solve Lagragian equation in the absence of time. Please help.
 
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superpig10000 said:
I set up a Lagragian equation that involves time t. What do I do? I only know how to solve Lagragian equation in the absence of time. Please help.
Here is one example. If you can justify the throw-away in section 1.3, perhaps you can do something similar.

http://physics.technion.ac.il/~avron/classical-mechanics/kapitza-wbct.pdf
 
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I understand the throw away, but when I differentiate

dL/dq - d/dt (dL/dq dot) = 0

do I care about time at all?
 
superpig10000 said:
I understand the throw away, but when I differentiate

dL/dq - d/dt (dL/dq dot) = 0

do I care about time at all?
If your (dL/dq dot) is a function of time, then why would you not care? I think once you have the simplified Lagarangian you do what you always do. It's been a long time since I did this stuff, but I don't see any reason to deviate from the example.
 
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