$\"\"$

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The function is $\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Again apply derivative on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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

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$\"\"$

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$\"\"$

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$\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$ .

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

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$\"\"$

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$\"\"$ .

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

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$\"\"$

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The functions are $\"\"$ and $\"\"$ .

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$\"\"$ .

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$\"\"$ .

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Consider $\"\"$ .

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

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$\"\"$

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$\"\"$ .

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Substitute $\"\"$ in above equation.

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$\"\"$

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$\"\"$ .

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Consider $\"\"$

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

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$\"\"$

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$\"\"$ .

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Substitute $\"\"$ in above equation.

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$\"\"$

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$\"\"$ .

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Therefore, the values of $\"\"$ , $\"\"$ and $\"\"$ are equal at $\"\"$ .

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$\"\"$

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Graph:

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Graph the functions $\"\"$ , $\"\"$ and $\"\"$ . $\"\"$ .

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Observe the graph:

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The values of $\"\"$ , $\"\"$ and $\"\"$ are equal at $\"\"$ .

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The values of $\"\"$ , $\"\"$ and $\"\"$ and their first derivatives agree at $\"\"$ .

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$\"\"$

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The values of $\"\"$ , $\"\"$ and $\"\"$ and their first derivatives agree at $\"\"$ .