$\"\"$

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(a)

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Consider the function as $\"\"$ .

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

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$\"\"$

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If $\"\"$ , then $\"\"$ .

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Therefore, $\"\"$ .

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Hence the function $\"\"$ is increasing for $\"\"$ .

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Thus, $\"\"$ for $\"\"$ .

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$\"\"$ if $\"\"$ .

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$\"\"$

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(b)

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If $\"\"$ , then $\"\"$ .

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Therefore, we have $\"\"$ .

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Comparison property of integrals :

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If $\"\"$ for $\"\"$ , then $\"\"$ .

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$\"\"$

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If $\"\"$ , then $\"\"$ .

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$\"\"$

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$\"\"$ .

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Observe the results of $\"\"$ and $\"\"$ .

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$\"\"$ .

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$\"\"$

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(a) $\"\"$ if $\"\"$ .

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(b) $\"\"$ .