is there a good website on how to do optimization online?? we learning this section now in our calc class but our teacher didn't really explain anything, he only did one example and told us the rest were all similar but i din't know where to even begin on some of then... #2. A company must manufacture a closed rectangular box with a square base. The volume must be 1040 cubic inches. The top and the bottom squares are made of a material that costs 3 dollars per square inch. The vertical sides are made of a different material that costs 4 per sqare inch. What is the minimal cost of a box of this type? for this one V=lwd v=l^2w w=1040/l^2 so the v=4(l^2)*3(1040/l^2) i know i take the derivative after this but where do i go from there?? #3. Find the rectangle of largest area that can be inscribed in a semicircle of diameter 199, assuming that one side of the rectangle lies on the diameter of the semicircle. The largest possible area is? i'm not even sure what this question is asking of me... so someone understand this???