Have you ever wondered why the cover of a manhole is nearly always round? Why isn’t it oval or square? Reuleaux curve based on an equilateral triangle. Reuleaux curves based on the pentagon (top) and ...

The three angles in a triangle add up to \(180^\circ\). If two of the angles are known then the third can be calculated by following these steps: Add the two known angles together. Subtract the total ...

THE principal novelties in this tract are the chapters on the orthopole (with some original propositions by the author) and on orthogonal projection (mostly after Prof. Neuberg). A pretty theorem in ...