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Colon


The colon is the symbol ":". It is used in a number of different ways in mathematics.

1. To denote ratio or odds, as in 2:1 (voiced "two to one").

2. To mean such that in constructions such as {x:x>0} (voiced "the set of numbers x such that x>0).

3. To give a name to a map, e.g., f:x|->x^2 (which is equivalent to the function notation f(x)=x^2).

4. As a part of the symbol A:=B sometimes used to mean "A is defined as B."

5. To delineate the three elements of trilinear coordinates, i.e., alpha:beta:gamma.

6. To indicate an extension field degree of an extension field K/F, denoted [K:F].

7. To denote colon product of two dyads.


See also

Colon Product, Semicolon, Such That

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References

Grossman, J. (Managing Ed.). "Colon." §5.97-5.104 in The Chicago Manual of Style, 14th ed. Chicago, IL: University of Chicago Press, pp. 182-185, 1993.

Referenced on Wolfram|Alpha

Colon

Cite this as:

Weisstein, Eric W. "Colon." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Colon.html

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