\"\"

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From the diagram the acute angles are \"\" and \"\".

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The sine and cosine values at \"\" are \"\".\"\"

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\"\"

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\"\"

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\"\" \ \ \"\"

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The sine and cosine values at \"\" are \"\".

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\"\"

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\"\" \ \

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\"\"

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\"\"      \"\"

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The sine and cosine values at \"\" and \"\" are \"\", \"\", 

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\"\" and \"\".