[RO]
Gheorghe Țițeica (n. 4/17 octombrie 1873, Drobeta Turnu-Severin - d. 5 februarie 1939, București) a fost un matematician și pedagog român, profesor la Universitatea din București și la Școala Politehnică din București, membru al Academiei Române și al mai multor academii straine, doctor honoris causa al Universității din Varșovia.
Este creator al unor capitole din geometria diferențială proiectivă și afină, unde a introdus noi clase de suprafețe, curbe și rețele care îi poartă numele. Prin numeroasele lucrări de matematică elementară și de popularizare a științei, pe care le-a publicat de-a lungul întregii sale vieți, a contribuit la ridicarea nivelului învățământului matematic din România.
Împreună cu Ion Ionescu, A. Ioachimescu și V. Cristescu, a înființat revista Gazeta matematică, iar cu G.G. Longinescu publicația Natura pentru răspândirea științelor. Cu D. Pompeiu a editat revista Mathematica.
Se dau trei cercuri cu centrele în O1, O2, O3, cu un punct comun M şi raze egale r=14.61m. Celelalte trei puncte A, B, C definesc la rândul lor un alt cerc.
Se cere:
- nnn=AABC (aria cercului descris de punctele A, B, C)
- eee= 2/3 * CABC (circumferinţa cercului descris de punctele A, B, C)
Pentru calcule se consideră:
π = pi = 3.14159
Din rezultatele finale se ia în considerare doar partea întreagă (fără rotunjire).
Obs: "aşa pare să fie" ... dar eşti sigur? Da/Nu? De ce?
N44° 26.nnn
E26° 06.eee
[EN]
Gheorghe Țițeica (4 October 1873 in Turnu Severin – 5 February 1939) publishing as George or Georges Tzitzeica) was a Romanian mathematician with important contributions in geometry. He is recognized as the founder of the Romanian school of differential geometry.
He showed an early interest in science, as well as music and literature. Țițeica was an accomplished violinist, having studied music since childhood: music was to remain his hobby. While studying at the Carol I High School in Craiova, he contributed to the school's magazine, writing the columns on mathematics and studies of literary critique.
In 1897, on the advice of teachers and friends, Țițeica completed his studies at a preparatory school in Paris. Among his mates were Henri Lebesgue and Paul Montel. On June 30, 1899 he defended his doctoral thesis titled Sur les congruences cycliques et sur les systemes triplement conjugues, on the framework of oblique curvature, before a board of examiners led by Gaston Darboux.
Upon his return to Romania, Țițeica was appointed assistant professor at the University of Bucharest. He was promoted to full professor on 4 May 1900, retaining this position until his death in 1939. He also taught mathematics at the Polytechnic University of Bucharest. In 1913, at age 40, Țițeica was elected as a permanent member of the Romanian Academy, replacing Spiru Haret.
The scientific work of Țițeica counts about 400 volumes, of which 96 are scientific projects, most addressing problems of differential geometry. Carrying the researches of the American geometer of German origin Ernest Wilczynski, Țițeica discovered a new category of surfaces and a new category of curves which now carry his name; his contributions represent the beginning of a new chapter in mathematics, namely the affine differential geometry. He also studied R-networks in n-dimensional space, defined through Laplace equations.
Given three circles centered at O1, O2, O3, having a common point M and equal radiuses r=14.61m. The other three points A, B, C define a different circle.
Compute the following:
- nnn=AABC (area of circle defined by points A, B, C)
- eee= 2/3 * CABC (circumference of circle defined by points A, B, C)
Accepted aproximations:
π = pi = 3.14159
From the final result keep only the integer part without rounding.
Note: "seems like it" ... but are you sure? Yes/No? Why?
N44° 26.nnn
E26° 06.eee
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