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Hi Mr Sasho,

I'd like to know how to solve exercice number (5)in:

http://www.umanitoba.ca/student/exams/site/data/136151-121200-F-851401618.pdf

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V=volume

x,x,y = dimensions of the box

S=area of the box (no lid).

V=x^{2}y

S=x^{2}+4xy

It is given that S=1200 so that x^{2}+4xy=1200 and so y=(1200-x^{2})/4x. Put this in the formula for the volume to get V=x^{2}(1200-x^{2})/4x, and use our theory to find the absolute maximum of that function.