Extended Real Number Line

Extended Real Number Line

In mathematics, the affinely extended real number system is obtained from the real number system R by adding two elements: +∞ and −∞ (read as positive infinity and negative infinity respectively). The projective extended real number system adds a single object, ∞ (infinity) and makes no distinction between "positive" or "negative" infinity. These new elements are not real numbers. It is useful in describing various limiting behaviors in calculus and mathematical analysis, especially in the theory of measure and integration. The affinely extended real number system is denoted R or .

When the meaning is clear from context, the symbol +∞ is often written simply as ∞.

Read more about Extended Real Number Line:  Order and Topological Properties, Arithmetic Operations, Algebraic Properties, Miscellaneous

Famous quotes containing the words extended, real, number and/or line:

    No: until I want the protection of Massachusetts to be extended to me in some distant Southern port, where my liberty is endangered, or until I am bent solely on building up an estate at home by peaceful enterprise, I can afford to refuse allegiance to Massachusetts, and her right to my property and life. It costs me less in every sense to incur the penalty of disobedience to the State than it would to obey. I should feel as if I were worth less in that case.
    Henry David Thoreau (1817–1862)

    The real test of a man is not how well he plays the role he has invented for himself, but how well he plays the role that destiny assigned to him.
    Jan Patocka (1907–1977)

    There are crimes which become innocent and even glorious through their splendor, number and excess.
    François, Duc De La Rochefoucauld (1613–1680)

    Today, the notion of progress in a single line without goal or limit seems perhaps the most parochial notion of a very parochial century.
    Lewis Mumford (1895–1990)