$\"\"$

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The trigonometric functon is $\"\"$ .

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First convert the angle to decimal degree form.

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$

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Using the scientific calculator : $\"\"$ .

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Using the graphing calculator : $\"\"$ . $\"\"$

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The value of $\"\"$ .