$\"\"$

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Find $\"\"$ .

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The trigonometric function is $\"\"$ .

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Consider $\"\"$ .

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Rewrite the expression as $\"\"$ .

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Apply odd-even identity : $\"\"$ .

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$\"\"$

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Apply co-function identity : $\"\"$ .

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$\"\"$ .

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Thus, the value of $\"\"$ .

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$\"\"$

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The value of $\"\"$ .