$\"\"$

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The function is $\"\"$ .

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The function has local maximum is $\"\"$ and local minimum is $\"\"$ .

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Since $\"\"$ , $\"\"$ .

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$\"\"$

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Since $\"\"$ ,

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$\"\"$ .

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$\"\"$

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The function is $\"\"$ .

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

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$\"\"$

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$\"\"$ .

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Since $\"\"$ , $\"\"$ .

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$\"\"$

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Since $\"\"$ , $\"\"$ .

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$\"\"$

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Solve the above equations using four variable calculator.

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$\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

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Substitute the above values in the function.

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$\"\"$ .

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$\"\"$

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The cubic function is $\"\"$ .