$\"\"$

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Product rule for derivatives: If $\"\"$ and $\"\"$ are differentiable at $\"\"$ , then

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$\"\"$ .

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The function is $\"\"$ .

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Consider $\"\"$ and $\"\"$ .

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$\"\"$

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

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$\"\"$

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$\"\"$ .

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Consider $\"\"$ .

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

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$\"\"$

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$\"\"$ .

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Apply product rule of derivative: $\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$ .

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The derivative of $\"\"$ is $\"\"$ .

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$\"\"$

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The derivative of $\"\"$ is $\"\"$ .