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In a beehive, each cell is a regular hexagonal prism, open at one end with a trihedral angle at the other end as in the figure. It is believed that bees form their cells in such a way as to minimize the surface area for a given side length and height, thus using the least amount of wax in cell construction. Examination of these cells has shown that the measure of the apex angle θ is amazingly consistent. Based on the geometry of the cell, it can be shown that the surface area S is given by
where s, the length of the sides of the hexagon, and h, the height, are constants.
- (a) Calculate dS/dθ.
- (b) What angle should the bees prefer?
- (c) Determine the minimum surface area of the cell (in terms of s and h).
Note: Actual measurements of the angle θ in beehives have been made, and the measures of these angles seldom differ from the calculated value by more than 2°.
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Single Variable Calculus
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