Step 1:

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The function is $\"\"$ .

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Apply partial derivative on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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The function is $\"\"$ .

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Apply partial derivative on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Find critical points, solve $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .

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The critical point $\"\"$ .

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$\"\"$ .

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Completing the squares.

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$\"\"$

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The function $\"\"$ has a relative minimum at $\"\"$ if $\"\"$ .

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$\"\"$ .

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The function has relative minimum at $\"\"$ .

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Step 2:

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$\"\"$

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Apply partial derivative on each side with respect to $\"\"$ . \ \

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$\"\"$

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$\"\"$

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$\"\"$

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