$\"\"$

\

The quotient rule for derivatives is

\

$\"\"$ .

\

Consider Right hand side.

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$\"\"$ .

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Add and subtract $\"\"$ in the numerator.

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$\"\"$

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$\"\"$

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$\"\"$

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Since $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .