operations factor
61Matrix multiplication — In mathematics, matrix multiplication is a binary operation that takes a pair of matrices, and produces another matrix. If A is an n by m matrix and B is an m by p matrix, the result AB of their multiplication is an n by p matrix defined only if… …
62guerrilla warfare — the use of hit and run tactics by small, mobile groups of irregular forces operating in territory controlled by a hostile, regular force. [1835 45] * * * ▪ military tactics Introduction also spelled guerilla warfare type of warfare fought …
63Commutative ring — In ring theory, a branch of abstract algebra, a commutative ring is a ring in which the multiplication operation is commutative. The study of commutative rings is called commutative algebra. Some specific kinds of commutative rings are given with …
64Media and Publishing — ▪ 2007 Introduction The Frankfurt Book Fair enjoyed a record number of exhibitors, and the distribution of free newspapers surged. TV broadcasters experimented with ways of engaging their audience via the Internet; mobile TV grew; magazine… …
65Medici Bank — For the private bank in Austria that failed due to its investment in Bernard Madoff s Ponzi scheme, see Bank Medici. Medici Bank Industry Banking Key people Giovanni di Bicci, Cosimo de Medici, Piero di Cosimo, Lorenzo de Medici, Francesco… …
66Hard disk drive — Hard drive redirects here. For other uses, see Hard drive (disambiguation). Hard disk drive Mechanical interior of a modern hard disk drive Date invented 24 December 1954 [1] …
67Iraq — /i rak , i rahk /, n. a republic in SW Asia, N of Saudi Arabia and W of Iran, centering in the Tigris Euphrates basin of Mesopotamia. 22,219,289; 172,000 sq. mi. (445,480 sq. km). Cap.: Baghdad. Also, Irak. * * * Iraq Introduction Iraq Background …
68Ukraine — /yooh krayn , kruyn , yooh krayn/, n. a republic in SE Europe: rich agricultural and industrial region. 50,684,635; 223,090 sq. mi. (603,700 sq. km). Cap.: Kiev. Russian, Ukraina. Formerly, Ukrainian Soviet Socialist Republic. * * * Ukraine… …
69Latin America, history of — Introduction history of the region from the pre Columbian period and including colonization by the Spanish and Portuguese beginning in the 15th century, the 19th century wars of independence, and developments to the end of World War II.… …
70technology, history of — Introduction the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …
