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The equations of the parabolas are \"\" and \"\".

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Consider the distance between the two parabolas be \"\".

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Hence \"\".

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\"\"

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The distance is minimum when its first derivative becomes zero.

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Apply derivative on each side with respect to \"\".

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\"\"

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Equate \"\" to zero.

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\"\"

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Substitute \"\" in \"\".

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\"\"

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Therefore the minimum vertical distance is \"\".

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The minimum vertical distance is \"\".