Real number | Real (English)
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Definition (keystage 3)
A real number, also called just a real, is a number which can be written out as a decimal, even though it might take forever to do so.
We use the symbol R for the set of all real numbers x=k.x1x2x3... where k is an integer and each of the xi is one of the digits 0, 1, ...9.
Whole numbers, fractions, irrational and transcendental numbers are all real.
We use the symbol R for the set of all real numbers x=k.x1x2x3... where k is an integer and each of the xi is one of the digits 0, 1, ...9.
Whole numbers, fractions, irrational and transcendental numbers are all real.
Definition (keystage 4)
R is the smallest set of numbers that contains the rationals Q together with the limits of all bounded increasing sequences in Q.
Relations
- broader:
- (en) Complex number
- (en) Number
- narrower:
- (en) Algebraic number
- (en) Argument of a complex number
- (en) Directed number
- (en) Error
- (en) Feigenbaum number
- (en) Feigenbaum's number
- (en) Irrational number
- (en) Lower bound
- (en) Modulus of a number
- (en) Modulus of a vector
- (en) Norm of a matrix
- (en) Nothing
- (en) Particular values of trigonometric functions
- (en) Percent
- (en) Radius of convergence
- (en) Rational
- (en) Rayleigh quotient
- (en) Reciprocal
- (en) Signed number
- (en) Upper bound
- (en) Whole number
- referenced:
- (en) x
- (en) Cauchy-Schwarz-Bunyakovski inequality
- (en) Comparable
- (en) Number line
- see also:
- (en) Counting number
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