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(a)

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The $\"\"$

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Differentiate on each side with respect to $\"\"$ .

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Chain rule of derivatives: $\"\"$ .

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$\"\"$ .

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Find the value of $\"\"$ at $\"\"$ .

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Obtain the required values from the table.

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$\"\"$

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$\"\"$ .

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(b)

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The function is $\"\"$ .

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Differentiate on each side with respect to $\"\"$ .

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Chain rule of derivatives: $\"\"$ .

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$\"\"$ .

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Find the value of $\"\"$ at $\"\"$ .

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Obtain the required values from the table.

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$\"\"$

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$\"\"$ .

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(a) $\"\"$ .

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(b) $\"\"$ .