\"\"

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The terminal side of the angle is in quadrant \"\".

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Since the angle lies in quadrant \"\", \"\".

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When the angle is doubled, \"\".

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Therefore, \"\" lies in quadrant \"\" and \"\".

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When the angle is halved, \"\".

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Hence, \"\".

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Therefore, \"\" lies in quadrant \"\".

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\"\"

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\"\" lies in quadrant \"\" and \"\".

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\"\" lies in quadrant \"\".