2015-04-30
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From the History of Computers
In our country the first adding machine came into being as far back as 1770 in Byelorussia. The words on this machine testify that it was devised and fabricated by Yakobson, a watchmaker and mechanic in a small provincial town.
P. Chebishev, Russian mathematician (1821-1894), was interested in calculators. Among many other mechanisms invented by him there was an arithmometer designed in 1876. In 1912 Academician A. Krilov (1863-1945) constructed a mechanical integrator for solving differential equations.
The first Soviet computer, a small-size electronic computing machine (MESM), was tested at Kiev Electrical Engineering Institute in 1950 under Academician S. Lebedev. In October 1951 it was put into operation. MESM was followed by BESM (a large-size electronic computing machine) in autumn 1952.
Serial production of computers in the USSR has been started since 1953. 1958 witnessed the production of M-20, computers of the first generation.
The 1st generation of electron tube computers was followed by the 2nd generation of transistor computers or those using magnetic logic elements.
In the 60's nearly 30 models of semiconductor computers were developed in our country. Starting with 1964 semiconductor computers — URAL, BESM-4 and M-220 were produced.
In the late 60's together with other members of the Council of Mutual Economic Assistance (CMEA) the Soviet Union started on the program of Unified Computer System, the program concerned with the 3d generation of computers with high-speed performance and program compatibility, which means that routines of less powerful computers can be carried out by larger ones. It was in 1972 that automatic sequence manufacture of these computers began.
Задание 5. Прочитайте и напишите словами следующие дроби:
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¾, ⅜, ¼, ⅔, 1 ½, ⅓, 4 ⅓, 2 ¾, 2 ⅔, 5 ⅞, 5 ¾, 8 ⅔, 0,105 литра, 2,18 фунта, 17,562 тонны, ⅞ тонны, ⅝ километра, 3 ⅓ тонны, 2 5/6 метра, 5%, 23%, 0,36%, 2,5%.
Задание 6. Прочитайте и напишите словами следующие уравнения и формулы:
| 11+23=34 456-27=429 8+5≠10 2∙2≠5 8∙8=64 49:7=7 2⅔∙10 ³√27+√25=8 x≥64 y≤38 √121 ³√64 | √25=5 4x=66 y=6/(x+3) y=-4,5x ⅔∙⅝ ³√8=2 5,6:2,5 5,6∙2,5 ⅞-⅜ 2x/3=9 (2c-10)/9+c/4 0,8x-(0,7x+0,36)=7,1 | x-0,5=2(0,3x-0,2) -10<-4,6<0 -6<m<-15 y/6=1/3 5³∙25 a+b=b+a ab=ba (a+b)+c=a+(b+c) (ab)c=a(bc) a(b+c)=ab+ac S=a² |
