Andrew Seaby
Is there a term for the shape shown above: a smooth, continuous curve with three axes of symmetry? And if anyone could share the equation for this curve, I would be very grateful.
Chris Daniel
Glan Conwy, Conwy, UK
The plate appears to be a smoothed Reuleaux triangle. A Reuleaux triangle, named after 19th-century German engineer Franz Reuleaux, has a constant width and is formed of three intersecting arcs, each one being centred on the opposite vertex of an equilateral triangle. The vertices of the triangle are points.
A smoothed Reuleaux triangle – that is, one with rounded vertices…
