So a friend of a friend calls me with this Cal. I. prob. I try to figure it out and get stuck. I have already told her that I don't know how to solve it. Now I am reallllyy curious on how to solve it. Here it goes:(adsbygoogle = window.adsbygoogle || []).push({});

You have a rectangular beam. Its cross-section has dimensions "l" and "w". The strength of the beam is directly proportional to w^2*l. Now if the beam is cut from a circular log with diameter of 3ft, what are the dimensions of the beam that will make it the strongest?

So I said s(w,l)= k*w^2*l where "s" is the strength. The width must be a little less than 3ft...but here I am just guessing. I know that l*w is proportional to pi*r^2, but I don't know where to go from there. help

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# Who else but pf could help me w/this prob.

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