Why does the partial of 2y^2e^(xy^2) equal 4ye^(xy^2)?

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The discussion centers on calculating the partial derivative of the function 2y^2e^(xy^2) with respect to y. The correct application of the product and chain rules reveals that the derivative results in 4ye^(xy^2), where the factor of 4y arises from differentiating 2y^2 and the exponential term remains unchanged due to the nature of its derivative. The participant initially confused the process but clarified that the exponential function's derivative retains its form. The conversation emphasizes the importance of correctly applying differentiation rules to achieve accurate results. Understanding these rules is crucial for solving similar problems in calculus.
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\frac{\partial_P}{\partial_y}(2ysinxcosx-y+2y^2e^{(xy^2)}

I worked the first part no problem, but the second part I needed a little help from my calculator. This is what I got:

2sinxcosx-1+4ye^{(xy^2)}

My question is, why does the partial of 2y^2e^{(xy^2)} come out to 4ye^{(xy^2)}?

I see the where the 4y comes from, but how come the e^{(xy^2)} stays exactly the same.

I also know that \frac{d}{dx}(e^x) = e^x

Thanks!
 
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It's a mistake in the last term of the sum.

\frac{\partial}{\partial y} 2y^2 e^{xy^2}

should be done using product rule and chain rule.

Daniel.
 
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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