Real Number
The set of all Rational and Irrational numbers is called the realnumbers, or simply the ``reals,'' and denoted 
. The set of real numbers is also called the Continuum, denoted
.
The real numbers can be extended with the addition of the Imaginary Number i, equal to 
. Numbersof the form 
, where 
and 
are both real, are then called Complex Numbers. Anotherextension which includes both the real numbers and the infinite Ordinal Numbers ofGeorg Cantor 
is the Surreal Numbers.
Pick two real numbers and at random in 
with a Uniform Distribution. What is the Probability
that 
, where 
denotes Nint, the nearest Integer to 
, is Even? The answer maybe found as follows (Putnam Exam).
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|  | (1) |
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|  | ||
|  | (2) |
Plouffe's ``Inverse Symbolic Calculator'' includes a huge database of 54 million real numbers which are algebraically relatedto fundamental mathematical constants and functions.
See also Complex Number, Continuum, i, Imaginary Number, Integer Relation, RationalNumber, Real Part, Surreal Number
References
Plouffe, S. ``Inverse Symbolic Calculator.'' http://www.cecm.sfu.ca/projects/ISC/. Plouffe, S. ``Plouffe's Inverter.'' http://www.lacim.uqam.ca/pi/. Putnam Exam. Problem B-3 in the 54th Putnam Exam.
- Cubocycloid
- Cubohemioctahedron
- Cuboid
- Cullen Number
- Cumulant
- Cumulant-Generating Function
- Cumulative Distribution Function
- Cundy and Rollett's Egg
- Cunningham Chain
- Cunningham Function
- Cunningham Number
- Cunningham Project
- Cupola
- Cupolarotunda
- Curl
- Curlicue Fractal
- Curl Theorem
- Current
- Curtate Cycloid
- Curtate Cycloid Evolute
- Curvature
- Curvature Center
- Curvature Scalar
- Curvature Vector
- Curve