\"\"

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The parametric equations of an ellipse are \"\" and \"\".

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Eliminate the parameter \"\":

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Consider \"\".

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\"\"

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Consider \"\".

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\"\"

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\"\"

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Trigonometric identity: \"\"

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Substitute \"\" and \"\" in above equation.

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\"\"

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The equation of an ellipse is \"\"

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\"\"

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The equation of an ellipse is \"\"