Zenodorus ( el, Ζηνόδωρος; c. 200 – c. 140 BC) was an ancient Greek mathematician.

Life and work

Little is known about the life of Zenodorus, although he may have befriended Philonides and made two trips to Athens, as described in Philonides' biography. From the style of his writing, it is known that he lived not much later than

Archimedes Archimedes of Syracuse (;; ) was a Greek mathematician, physicist, engineer, astronomer, and inventor from the ancient city of Syracuse in Sicily. Although few details of his life are known, he is regarded as one of the leading scientists i ...

. He is mentioned in Diocles' ''On Burning Mirrors'':

And when Zenodorus the astronomer came down to Arcadia and was introduced to us, he asked us how to find a mirror surface such that when it is placed facing the sun the rays reflected from it meet a point and thus cause burning.

Zenodorus is known for authoring the treatise ''On isoperimetric figures'', now lost. Many of its propositions are known from

Theon of Alexandria Theon of Alexandria (; grc, Θέων ὁ Ἀλεξανδρεύς; 335 – c. 405) was a Greek scholar and mathematician who lived in Alexandria, Egypt. He edited and arranged Euclid's ''Elements'' and wrote commentaries on works ...

's commentary on

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...

's ''Syntaxis''. In his ''On isoperimetric figures'', Zenodorus studies the areas and perimeters of different geometric figures. The most important propositions proved by him are that, # Of all regular polygons of equal perimeter, that is the greatest in area which has the most angles. # A circle is greater than any regular polygon of equal contour. # Of all polygons of the same number of sides and equal perimeter the equilateral and equiangular polygon is the greatest in area. # Of all solid figures the surfaces of which are equal, the sphere is the greatest in solid content..Kline (1972), p. 126

Notes

References

* * Morris Kline, ''Mathematical Thought From Ancient to Modern Times'', Oxford University Press, 1972. * G. J. Toomer, ''Diocles On Burning Mirrors, Sources in the History of Mathematics and the Physical Sciences 1'' (New York, 1976).

External links

*
History of the Isoperimetric Problem
a
Convergence
{{DEFAULTSORT:Zenodorus Ancient Greek mathematicians 2nd-century BC Greek people 200s BC births 140s BC deaths 2nd-century BC mathematicians