$\"\"$

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The function $\"\"$ .

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

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$\"\"$

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Apply quotient rule $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ on $\"\"$ .

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$\"\"$ is monotonic decreasing on $\"\"$ therefore $\"\"$ has an inverse.

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$\"\"$

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The real number $\"\"$ .

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Find $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .