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Definite integral is $\"\"$ .

Find the integral using integration by parts.

Formula for integration by parts: $\"\"$ .

Here $\"\"$ and $\"\"$ .

Consider $\"\"$ .

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

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Consider $\"\"$ .

Apply integral on each side.

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$\"\"$ .

Substitute corresponding values in integration by parts formula.

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As odd multiples of cosine is $\"\"$ and even multiples of cosine is $\"\"$ .

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