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Use the chain rule to find ∂z/∂s and ∂z/∂t.
z = x⁵y⁵, x = s cos t, y = s sin t

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Final answer:

To find ∂z/∂s and ∂z/∂t using the chain rule is ∂z/∂s = 5x⁴y⁵ * cos t + 5x⁵y⁴ * sin t and ∂z/∂t = -5x⁴y⁵ * s sin t + 5x⁵y⁴ * s cos t.

Step-by-step explanation:

To find ∂z/∂s and ∂z/∂t using the chain rule, we need to differentiate z with respect to s and t separately.

Let's start with ∂z/∂s. Using the chain rule, we have:

∂z/∂s = ∂z/∂x * ∂x/∂s + ∂z/∂y * ∂y/∂s

Since z = x⁵y⁵, we can find ∂z/∂x and ∂z/∂y using the power rule:

∂z/∂x = 5x⁴y⁵

∂z/∂y = 5x⁵y⁴

Now, let's find ∂x/∂s and ∂y/∂s. Given x = s cos t and y = s sin t, we can differentiate them with respect to s:

∂x/∂s = cos t

∂y/∂s = sin t

Substituting these values into the chain rule equation, we get:

∂z/∂s = 5x⁴y⁵ * cos t + 5x⁵y⁴ * sin t

Similarly, to find ∂z/∂t, we differentiate z with respect to t:

∂z/∂t = ∂z/∂x * ∂x/∂t + ∂z/∂y * ∂y/∂t

Following the same steps as above, we find:

∂z/∂t = -5x⁴y⁵ * s sin t + 5x⁵y⁴ * s cos t

In summary, using the chain rule, we found ∂z/∂s = 5x⁴y⁵ * cos t + 5x⁵y⁴ * sin t and ∂z/∂t = -5x⁴y⁵ * s sin t + 5x⁵y⁴ * s cos t.

User Jared Forsyth
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