Step 1:

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The function is $\"\"$ .

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Formula for $\"\"$ .

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Here $\"\"$ , $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in $\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Find

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Increme

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$\"\"$

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The function is $\"\"$ .

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

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The total differential is $\"\"$ .

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

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The above expression is in the form of $\"\"$ .

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Find $\"\"$ and $\"\"$ .

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$\"\"$ .

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

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$\"\"$

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$\"\"$ .

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

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$\"\"$ \ \

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$\"\"$ .

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

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$\"\"$ \ \

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Substitute $\"\"$ .

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$\"\"$ \ \

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$\"\"$

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$\"\"$

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Linear approximation $\"\"$

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Here $\"\"$ and $\"\"$ in above formula. \ \

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$\"\"$

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$\"\"$

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$\"\"$

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Solution:

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$\"\"$ .

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