$\"\"$

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The trigonometric identity is $\"fraction$ .

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Consider $\"\"$ .

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Take out $\"begin$ as a common term.

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$\"equal$ )

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Apply pythagorean identity: $\"begin$ .

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$\"equal$ \ \

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$\"equal$ \ \

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$\"Syntax$

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Apply quotient identity: $\"fraction$ .

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$\"Syntax$

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$\"fraction$ .

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$\"\"$

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$\"fraction$ .