Partial Derivatives of x^2yz+3y-xcos(3yz): df/dx and df/dy Solutions

Thread starter cabellos
Start date Nov 5, 2006

AI Thread Summary

The discussion focuses on finding the partial derivatives of the function f(x,y,z) = x^2yz + 3y - xcos(3yz). The user successfully calculated the partial derivatives as df/dx = 2xyz - cos(3yz) and df/dy = x^2z + 3 + 3xzsin(3yz). Other participants confirm the correctness of these solutions, emphasizing the importance of treating the other variables as constants during differentiation. The user is encouraged to proceed with the problem using these derivatives. Overall, the calculations and confirmations provide clarity for further steps in solving the problem.

Nov 5, 2006

cabellos

I have to find the 3 partial derrivatives of f(x,y,z) = x^2yz+3y-xcos(3yz)

I have solved for df/dx and df/dy and here are my solutions:

df/dx = 2xyz-cos3yz
df/dy = x^2z+3+3xzsin3yz

are these correct so i can continue with the problem?

Thanks for the help.

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Nov 5, 2006

arildno

Science Advisor

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Gold Member

Dearly Missed

Yup, they are!

Just treat the other variables as constants.

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