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Verify clairaut's theorem for u=e^xysiny

User Onurhb
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Final answer:

We verified Clairaut's Theorem for the function u=e^{xy}sin(y) by showing that the mixed partial derivatives with respect to x and y are indeed equal, which confirms the theorem's criteria for the given function.

Step-by-step explanation:

The student has asked to verify Clairaut's Theorem for a given function u=e^{xy}\sin(y). Clairaut's Theorem states that if a function u=f(x,y) has continuous second partial derivatives, then the mixed derivatives are equal, that is:

\[\frac{\partial^2 u}{\partial x \partial y} = \frac{\partial^2 u}{\partial y \partial x}\]

We first find the partial derivative of u with respect to x:

\[\frac{\partial u}{\partial x} = y e^{xy} \sin(y)\]

Then we take the partial derivative of this result with respect to y:

\[\frac{\partial^2 u}{\partial y \partial x} = e^{xy} \sin(y) + xy e^{xy} \cos(y)\]

Now, we reverse the order. We first find the partial derivative of u with respect to y:

\[\frac{\partial u}{\partial y} = xe^{xy} \sin(y) + e^{xy} \cos(y)\]

And then take the partial derivative of this result with respect to x:

\[\frac{\partial^2 u}{\partial x \partial y} = e^{xy} \sin(y) + xy e^{xy} \cos(y)\]

Both mixed derivatives are indeed equal, hence verifying Clairaut's Theorem for the given function u=e^{xy}\sin(y).

User Utopik
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User Arshpreet
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