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Gold is a chemical element with the symbol Au (from the Latin word aurum) and the atomic number 79. In its pure form, it is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactive chemical elements ...
History (derived from Ancient Greek ἱστορία (historía) 'inquiry; knowledge acquired by investigation') [1] is the systematic study and documentation of the human past. [2] [3] The period of events before the invention of writing systems is considered prehistory. [4] ". History" is an umbrella term comprising past events as well as the ...
Florence, birthplace of the Italian Renaissance.The architectural perspective and new systems of banking and accounting were introduced during the time. The Renaissance (UK: / r ə ˈ n eɪ s ən s / rən-AY-sənss, US: / ˈ r ɛ n ə s ɑː n s / REN-ə-sahnss) is a period in history and a cultural movement in Europe marking the transition from the Middle Ages to modernity.
Geologic time scale. The geologic time scale, proportionally represented as a log-spiral with some major events in Earth's history. A megaannus (Ma) represents one million (10 6) years. The geologic time scale or geological time scale ( GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating ...
United States dollar. The United States dollar ( symbol: $; currency code: USD; also abbreviated US$ to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official currency of the United States and several other countries.
Viète. de Moivre. Euler. Fourier. v. t. e. In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for which both sides of the equality are defined. Geometrically, these are identities involving certain functions of one or more angles.
The Middle Ages is the second of the three traditional divisions of Western history: antiquity, medieval, and modern. Major developments include the predominance of agriculture in the economy, the exploitation of the peasantry, slow interregional communication, the importance of interpersonal relations in power structures, and the fragility of ...
