I was wondering if someone could show me where to go next in this problem.(adsbygoogle = window.adsbygoogle || []).push({});

I need to determine the minimum length, width and height that a 1 cubic foot box can have. This box does not have a top. I know that I need to minimize the area, but I'm not sure if I'm going about this correctly. So far I have that A(l,w)=lw+2(1/l)+2(1/w). I made the substitution from three to two variables because V=lwh therefore h=1/lw.

I'm assuming that I need to take the derivative of the area equation, and then determine the minimum using the second derivative. Is this the correct procedure?

Thanks!

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# Homework Help: Determine the minimum using the second derivative

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