$\"\"$

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The integral is $\"\"$ .

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Let $\"\"$ , then $\"\"$ .

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$\"\"$

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Pythagorean identity : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ $\"\"$

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$\"\"$

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Consider $\"\"$ .

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Let $\"\"$ , then $\"\"$ .

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Let $\"\"$ , then $\"\"$ .

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Integration by parts formula : $\"\"$ .

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Substitute corresponding values in integral by parts formula.

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$\"\"$

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$\"\"$

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Consider $\"\"$ .

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$\"\"$

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

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$\"\"$

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$\"\"$ .

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From equation (1) :

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$\"\"$ .

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$\"\"$

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$\"\"$ .