I Time derivative using the quotient rule

AI Thread Summary
The discussion focuses on verifying the application of the quotient rule for taking the time derivative of a function involving time-dependent variables "r" and "theta." The original poster is seeking confirmation on their mathematical approach while working on a numerical mechanics problem. Responses indicate that the use of the quotient rule appears to be correct. The poster is encouraged to double-check their calculations to resolve discrepancies in their results. Overall, the thread emphasizes the importance of careful mathematical verification in problem-solving.
Mishal0488
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Hi Guys

Sorry for the rudimentary post. I am busy with a numerical solution to a mechanics problem, and the results are just not as expected. I am re-checking the mathematics to ensure that all is in order in doing so I am second guessing a few things

Referring to the attached scan, is the quotient rule used correctly when taking the time derivative of the function? Note that both "r" and "theta" are time dependent.

Thanks in advance
 

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