- Eudoxus of Cnidus
*(c. 400 bc–350 bc) Greek astronomer and mathematician*Born in Cnidus, which is now in Turkey, Eudoxus is reported as having studied mathematics under Archytas, a Pythagorean. He also studied under Plato and in Egypt. Although none of his works have survived they are quoted extensively by Hipparchus. Eudoxus was the first astronomer who had a complete understanding of the celestial sphere. It is only this understanding that reveals the irregularities of the movements of the planets that must be taken into account in giving an accurate description of the heavens. For Eudoxus the Earth was at rest and around this center 27 concentric spheres rotated. The outermost sphere carried the fixed stars, each of the planets required four spheres, and the Sun and the Moon three each. All these spheres were necessary to account for the daily and annual relative motions of the heavenly bodies. He also described the constellations and the changes in the rising and setting of the fixed stars in the course of a year.In mathematics, Eudoxus is thought to have contributed the theory of proportion to be found in Book V of Euclid – the importance of this being its applicability to irrational as well as rational numbers. The method of exhaustion in Book XII is also attributed to Eudoxus. This tackled in a mathematical way for the first time the difficult problem of calculating an area bounded by a curve.

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**Eudoxus of Cnidus**— (Greek Εὔδοξος ὁ Κνίδιος) (410 or 408 BC ndash; 355 or 347 BC) was a Greek astronomer, mathematician, scholar and student of Plato. Since all his own works are lost, our knowledge of him is obtained from secondary sources, such as Aratus s poem… … Wikipedia**Eudoxus of Cnidus**— ▪ Greek mathematician and astronomer Introduction born c. 395–390 BC, Cnidus, Asia Minor [now in Turkey] died c. 342–337 BC, Cnidus Greek mathematician and astronomer who substantially advanced proportion theory, contributed to the… … Universalium**EUDOXUS OF CNIDUS**— a Grecian astronomer, was a pupil of Plato, and afterwards studied in Egypt; said to have introduced a 365½ day year into Greece; flourished in the 4th century B.C … The Nuttall Encyclopaedia**Eudoxus of Cnidus**— /juˈdɒksəs əv ˈnaɪdəs/ (say yooh doksuhs uhv nuyduhs) noun 408?–355? BC, Greek scholar known for his works in astronomy, mathematics and philosophy … Australian English dictionary**Eudoxus**— was the name of two ancient Greeks:* Eudoxus of Cnidus (c. 408 BC – c.347 BC), Greek astronomer and mathematician. * Eudoxus of Cyzicus (fl. 130 BC), Greek navigator … Wikipedia**Eudoxus of Cyzicus**— Another article treats of Eudoxus of Cnidus. Eudoxus of Cyzicus (fl. c. 130 BC) (Greek: Ευδοξος) was a Greek navigator who explored the Arabian Sea for Ptolemy VIII, king of the Hellenistic Ptolemaic dynasty in Egypt.Voyages to IndiaAccording to… … Wikipedia**Eudoxus (lunar crater)**— lunar crater data latitude=48.7 N or S=N longitude=10.6 E or W=E diameter=37 km depth=3.4 km colong=344 eponym=Eudoxus of CnidusEudoxus is a prominent lunar impact crater that lies to the east of the northern tip of the Montes Caucasus range. It… … Wikipedia**Cnidus**— Cnidean, adj. /nuy deuhs/, n. an ancient city in SW Asia Minor, in Caria: the Athenians defeated the Spartans in a naval battle near here 394 B.C. * * * Ancient Greek coastal city, southwestern Anatolia. An important commercial centre and the… … Universalium**Eudoxos von Cnidus**— Eudoxos von Knidos (* 410 oder 408 v. Chr. in Cnidus, Kleinasien; † 355 oder 347 v. Chr. in Cnidus, Kleinasien) war ein griechischer Mathematiker, Astronom, Geograph und Arzt. Er war Schüler des Archytas und hatte mit Platon enge… … Deutsch Wikipedia**Kampyle of Eudoxus**— of:x^4=x^2+y^2,,or, in polar coordinates,:r= sec^2 heta,.This quartic curve was studied by the Greek astronomer and mathematician Eudoxus of Cnidus (c. 408 BC – c.347 BC) in relation to the classical problem of doubling the cube.ee also* List of… … Wikipedia