$\"\"$

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The integral is $\"\"$ .

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Integration by parts: $\"\"$ .

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Consider $\"\"$ and $\"\"$ .

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Consider $\"\"$ and $\"\"$ .

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Substitute the corresponding values in the formula.

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$\"\"$

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Consider $\"\"$

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As $\"\"$ then $\"\"$ .

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$\"\"$

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Apply derivative on each side with respect to $\"\"$ .

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$\"\"$ .

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Substitute the corresponding values.

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$\"\"$

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$\"\"$

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$\"\"$

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Double angle formula: $\"\"$

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$\"\"$

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Substiute the values of $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .