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Maximizing volume of a rectangular solid, given surface area
Maximize the volume of a rectangular solid, given that the sum of the areas of the six faces is 6a^2 for a constant 'a'.
So I know if its a rectangle, I have 6 sides... 2 sides are 'a x a' and 4 sides should be '2a x a'... but that gives me 2a^2 + 8a^2 = 10a^2 which is more than the given 6a^2... im not sure what im doing wrong or how to go about this question? Im pretty sure since its volume a triple integral is involved...