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Definition Finding the direction of the cross product by the right-hand rule The cross product of two vectors a and b is defined only in three-dimensional space and is denoted by a × b.In physics and applied mathematics, the wedge notation a ∧ b is often used (in conjunction with the name vector product), although in pure mathematics such notation is usually reserved for just the exterior ...
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 free encyclopedia that anyone can edit. After the Deluge is an oil painting by English artist George Frederic Watts. Completed in 1891, it shows a scene from the story of Noah's Flood, in which Noah opens the window of his Ark to see that after 40 days the rain has stopped. The Symbolist painting is a stylised seascape, dominated by a ...
In statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is. The parameter is the mean or expectation of the distribution (and also its median and mode ), while the parameter is its standard deviation.
The High-frequency Active Auroral Research Program ( HAARP) is a University of Alaska Fairbanks program which researches the ionosphere – the highest, ionized part of Earth's atmosphere . The most prominent instrument at HAARP is the Ionospheric Research Instrument (IRI), a high-power radio frequency transmitter facility operating in the high ...
The number π (/ p aɪ /; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159.The number π appears in many formulae across mathematics and physics.It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although fractions such as are commonly used to ...
Liu Cixin (Chinese: 刘慈欣; pinyin: Liú Cíxīn, pronounced [ljo ʊ tsʰɨ ɕi n]; English: / l j uː (t) s ə ˈ ʃ iː n /; born 23 June 1963) is a Chinese computer engineer and science fiction writer. He is a nine-time winner of China's Galaxy Award and has also received the 2015 Hugo Award for his novel The Three-Body Problem as well as the 2017 Locus Award for Death's End.
