The derivative using logarithmic differentiation. Is this correct?

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The discussion focuses on using logarithmic differentiation to find the derivative of a function. A participant questions the correctness of their solution, particularly addressing a mistake in the transition from the 5th to the 6th line regarding ln(e). They clarify that ln(e) equals 1, which simplifies their expression correctly. The final derivative calculation, resulting in d/dx(x) = 1, is confirmed as accurate. Overall, the use of logarithmic differentiation is validated in this context.
dylanhouse
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1. Homework Statement [/b]

Find the derivative of the given function.

Homework Equations



Chain rule and logarithmic differentiation.

The Attempt at a Solution



See attached .gif. I was just wondering if this seemed correct? Thanks!
 

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You made a small mistake going from the 5th to the 6th line. ln(e) = ?
 
ln(e) = 1. I replaced it in the 7th line.
 
dylanhouse said:
ln(e) = 1. I replaced it in the 7th line.

I mean, xln(e) = x(1) = x right?

\frac{d}{dx} (x) = 1
 
It looks fine to me as it is.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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