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  1. Big O notation is a mathematical notation that describes the limiting behavior of a function when the argument tends towards a particular value or infinity. Big O is a member of a family of notations invented by German mathematicians Paul Bachmann, [1] Edmund Landau, [2] and others, collectively called Bachmann–Landau notation or asymptotic notation.

  2. en.wikipedia.org › wiki › 55 - Wikipedia

    5 (five) is a number, numeral and digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. It has garnered attention throughout history in part because distal extremities in humans typically contain five digits. Five is the third-smallest prime number, and the second super-prime, since its prime ...

    • five
    • prime
    • 5th, (fifth)
    • quinary
  3. en.wikipedia.org › wiki › Ordered_pairOrdered pair - Wikipedia

    • Generalities
    • Informal and Formal Definitions
    • Defining The Ordered Pair Using Set Theory
    • Category Theory
    • See Also

    Let ( a 1 , b 1 ) {\displaystyle (a_{1},b_{1})} and ( a 2 , b 2 ) {\displaystyle (a_{2},b_{2})} be ordered pairs. Then the characteristic (or defining) propertyof the ordered pair is: The set of all ordered pairs whose first entry is in some set A and whose second entry is in some set B is called the Cartesian product of A and B, and written A × B....

    In some introductory mathematics textbooks an informal (or intuitive) definition of ordered pair is given, such as This is usually followed by a comparison to a set of two elements; pointing out that in a set a and bmust be different, but in an ordered pair they may be equal and that while the order of listing the elements of a set doesn't matter, ...

    If one agrees that set theory is an appealing foundation of mathematics, then all mathematical objects must be defined as sets of some sort. Hence if the ordered pair is not taken as primitive, it must be defined as a set. Several set-theoretic definitions of the ordered pair are given below( see also ).

    A category-theoretic product A × B in a category of sets represents the set of ordered pairs, with the first element coming from A and the second coming from B. In this context the characteristic property above is a consequence of the universal property of the product and the fact that elements of a set X can be identified with morphisms from 1 (a ...

    Trybulec, Andrzej, 1989, "Tarski–Grothendieck Set Theory", Journal of Formalized Mathematics(definition Def5 of "ordered pairs" as { { x,y }, { x } })
  4. en.wikipedia.org › wiki › Common_EraCommon Era - Wikipedia

    Common Era. Common Era ( CE) and Before the Common Era ( BCE) are year notations for the Gregorian calendar (and its predecessor, the Julian calendar ), the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the original Anno Domini (AD) and Before Christ (BC) notations used for the same calendar era.

  5. according to International Monetary Fund estimates [n 1] [1] Countries by nominal GDP in 2019 [n 2] > $20 trillion. $10–20 trillion. $5–10 trillion. $1–5 trillion. $750 billion – $1 trillion. $500–750 billion. $250–500 billion.

  6. en.wikipedia.org › wiki › Golden_ratioGolden ratio - Wikipedia

    The golden ratio's negative −φ and reciprocal φ−1 are the two roots of the quadratic polynomial x2 + x − 1. The golden ratio is also an algebraic number and even an algebraic integer. It has minimal polynomial. This quadratic polynomial has two roots, and. The golden ratio is also closely related to the polynomial.

  7. Canonical commutation rule for position q and momentum p variables of a particle, 1927. pq − qp = h / (2 πi ). Uncertainty principle of Heisenberg, 1927. The uncertainty principle, also known as Heisenberg's indeterminacy principle, is a fundamental concept in quantum mechanics. It states that there is a limit to the precision with which ...