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Step 1:

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The trigonometric function is $\"\"$ .

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Fundamental trigonometric identities: $\"\"$ .

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$\"\"$

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Rewrite the trigonometric function is $\"\"$ .

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Simplify the function.

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$\"\"$

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Fundamental trigonometric identities: $\"\"$ .

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$\"\"$

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$\"\"$

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Solution:

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The value of trigonometric function is $\"\"$ .

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