$\"\"$

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The function is $\"\"$ , where $\"\"$ is a constant.

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Corollary :

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If $\"\"$ for all values of $\"\"$ in the interval $\"\"$ , then $\"\"$ is a constant on $\"\"$ .

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$\"\"$ , where $\"\"$ is a constant.

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Consider the function is $\"\"$ .

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

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$\"\"$ .

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Therefore $\"\"$ .

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Apply the theorem.

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Then $\"\"$ is a constant.

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Consider $\"\"$ is a constant.

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$\"\"$

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Substitute $\"\"$ in above expression.

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$\"\"$ .

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$\"\"$

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$\"\"$ .