Hello.I recently discovered the Lagrangian aproach on classical mechanics ptovlems, such as a spring pendullum, or even on particle physics problems, and i think it s a really smart way of getting results. I'd like to aproach this method deeper and so my questions are the following: 1.What are the calculus operations that you need to master?From what I've seen you need derrivatives and partial derrivatives. 2.Coud you recommend me some rookie undergraduate course on Lagrangians?But nothing to stuffy. 3.I woud apreciate if you coud tell me your own opinion about this method.:) Thank you!