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Use the chain rule to find ∂z/∂s and ∂z/∂t for the function z = x³y⁹, where x = s cos(t) and y = s sin(t).

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Final answer:

To find ∂z/∂s and ∂z/∂t, we rewrite z in terms of s and t and apply the chain rule to find the partial derivatives. ∂z/∂s = 3(s cos(t))²(s sin(t))⁹ + 9(s cos(t))³(s sin(t))⁸(sin(t)), and ∂z/∂t = 9(s cos(t))³(s sin(t))⁸(-s sin(t)).

Step-by-step explanation:

To find the partial derivatives ∂z/∂s and ∂z/∂t using the chain rule, we start by expressing z in terms of s and t. Since x = s cos(t) and y = s sin(t), we can rewrite z = x³y⁹ as z = (s cos(t))³(s sin(t))⁹.

Next, we take the partial derivative with respect to s by treating t as a constant. This gives us ∂z/∂s = 3(s cos(t))²(s sin(t))⁹ + 9(s cos(t))³(s sin(t))⁸(sin(t)).

Finally, we take the partial derivative with respect to t by treating s as a constant. This gives us ∂z/∂t = 9(s cos(t))³(s sin(t))⁸(-s sin(t)).

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