$\"\"$

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(a)

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

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Consdier $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Assume $\"\"$ .

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For $\"\"$ , we have $\"\"$ .

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Therefore, $\"\"$

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$\"\"$

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From the results of $\"\"$ and $\"\"$ ,

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$\"\"$ .

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$\"\"$

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(b)

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Consider $\"\"$ .

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Comparison property of integrals :

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

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Therefore,

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$\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$ .

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$\"\"$

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(a) $\"\"$ .

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(b) $\"\"$ .