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Write a chain rule formula for the following derivative

∂w/∂t for w=f(x,y,z);x=g(r,s),y=h(t),z=k(r,s,t) .

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Final answer:

Using the chain rule for multivariable functions, the partial derivative \(\frac{\partial w}{\partial t}\) for w=f(x,y,z) is \(\frac{\partial w}{\partial y}\frac{\partial y}{\partial t} + \frac{\partial w}{\partial z}\frac{\partial z}{\partial t}\), neglecting \(\frac{\partial x}{\partial t}\) since x does not depend on t.

Step-by-step explanation:

To find the partial derivative \(\frac{\partial w}{\partial t}\) for w=f(x,y,z) where x=g(r,s), y=h(t), and z=k(r,s,t), we need to employ the chain rule for partial derivatives.

According to the chain rule for multivariable functions, the derivative of w with respect to t can be expressed as follows:

\(\frac{\partial w}{\partial t} = \frac{\partial w}{\partial x}\frac{\partial x}{\partial t} + \frac{\partial w}{\partial y}\frac{\partial y}{\partial t} + \frac{\partial w}{\partial z}\frac{\partial z}{\partial t}\)

But since x is not a function of t, its derivative with respect to t is zero, simplifying our formula:

\(\frac{\partial w}{\partial t} = \frac{\partial w}{\partial y}\frac{\partial y}{\partial t} + \frac{\partial w}{\partial z}\frac{\partial z}{\partial t}\)

In this formula, y and z are both functions of t, and we must compute their derivatives with respect to t separately:

\(\frac{\partial y}{\partial t}\) and \(\frac{\partial z}{\partial t}\)

After finding these, we can substitute them back into our chain rule expression to find the desired partial derivative of w with respect to t.

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