The illustration shows the figure known in mathematics as;
Tales' sails
Pythagorean sickles
Archimedes' arches
lune of Hippocrates,
In geometry, the lune of Hippocrates, named after Hippocrates of Chios, is a lune bounded by arcs of two circles, the smaller of which has as its diameter a chord spanning a right angle on the larger circle. Equivalently, it is a non-convex plane region bounded by one 180-degree circular arc and one 90-degree circular arc. It is the first curved figure to have its exact area calculated mathematically.
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Tales' sails
Pythagorean sickles
Archimedes' arches
lune of Hippocrates,
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