$\"\"$

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The equation is $\"\"$ .

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

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$\"\"$

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

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$\"\"$

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$\"\"$

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(a)

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Find $\"\"$ at $\"\"$ , $\"\"$ and $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the above equation.

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$\"\"$

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$\"\"$ .

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$\"\"$

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(b)

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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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Substitute the values $\"\"$ and $\"\"$ in the above expression.

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$\"\"$

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$\"\"$ .

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$\"\"$

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(a) $\"\"$ .

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(b) $\"\"$ .