$\"\"$

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The integral is $\"\"$ .

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Apply the double angle formula for $\"\"$ .

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$\"\"$ .

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

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$\"\"$

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Apply the sum and difference rule of integration : $\"\"$ .

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

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Consider the integral $\"\"$ .

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Apply integration by parts $\"\"$ .

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Where $\"\"$ .

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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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Subustiute $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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