Local minimum and Local maximum for a Functions of tow variables

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؟؟؟؟؟؟؟؟؟؟؟؟؟

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62 PAR 14
Find the shape of a rectangular box with no top having given volume V and the
least possible total surface area of its five faces

؟؟؟؟؟؟؟؟؟؟؟؟!!!!!

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