Hi, I would like some help in proving the following:(adsbygoogle = window.adsbygoogle || []).push({});

Consider the action for a particle in a potential U. Show that an extremum path is never that of a local maximum for the action.

I think what I have to do is look at the second derivative of the action integral. Then I should somehow argue that this value is always greater or equal zero, so that the extremum is never a local maximum. My problem is how to take the second derivative.

Thanks.

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# Lagrangian mechanics proof

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