$\"\"$

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The function is $\"\"$ .

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Apply derivative with respect to $\"\"$ .

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$\"\"$

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Apply the quotient rule of derivatives : $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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Find the derivative at the point $\"\"$ :

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .