On the maximum value of a multi-variable function (Q2080473)

The paper investigates how to plan a canal with maximal section capacity if we can use bricks of unit length. The main result is a direct consequence of the isoperimetrical problem for regular polygons. In fact, the paper creates an \textit{á posteriori} problem to an \textit{á priori} solution. For the entire collection see [Zbl 1485.65002].