$\"\"$

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Find $\"\"$ .

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The trigonometric functions $\"\"$ and $\"\"$ .

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Consider $\"\"$ .

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Apply reciprocal identity : $\"\"$ .

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$\"\"$ .

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Consider $\"\"$ .

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Apply quotient identity : $\"\"$ .

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$\"\"$

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$\"\"$

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The value of $\"\"$ .