Def. of Interval
   

   

 Math Help -> Calculus -> Theorems -> Intermediate value -> Definition of "interval" 

Definition of Interval

An Interval is a subset S of a totally ordered set T with the property that whenever
     - x and y are in S and
     - z is in T and
     - x < z < y
then z is in S.

A "totally ordered" set is a set over which the £ operator is reflexive, antisymmetric, transitive, and total...

reflexive:  a £
antisymmetric: if a £ b and b £ a then a = b 
transitive: if a £ b and b £ c then a £
total: a £ b or b £ a

The reflexive property restricts the meaning of the £ operator, and the other three properties are satisfied by the real numbers.

Internet References

Source: Wikipedia

Related Pages in this Website

Go back to Calculus Home or visit Calculus Theorems

Subdividing an Interval

Arithmetic Rules -- properties of equality, addition, multiplication, and in particular the Axioms of Real Arithmetic, including the completeness axiom.

Upper Bound -- definition of "upper bound" and "least upper bound" of either sets or functions

 

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