Let f be the function defined in Example 3.4.4. For each of the following, determine wheth...

Let f be the function defined in Example 3.4.4. For each of the following, determine whether the partial derivative exists; if it does, find its value.

(a)

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(b)

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(c)

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(d)

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(e)

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(f)

[Suggestion: Consult Figure 1.2.9(a).]