Cantor's construction of the real numbers/Definition
From Maths
< Cantor's construction of the real numbers
Revision as of 11:47, 2 June 2016 by Alec (Talk | contribs) (Created page with "<noinclude> {{Stub page|grade=A|msg=Somewhat badly written, demote to B once cleaned up}} ==Definition== </noinclude> The set of real numbers, {{M|\mathbb{R} }}, is the ...")
Stub grade: A
This page is a stub
This page is a stub, so it contains little or minimal information and is on a to-do list for being expanded.The message provided is:
Somewhat badly written, demote to B once cleaned up
Definition
The set of real numbers, [ilmath]\mathbb{R} [/ilmath], is the quotient space, [ilmath]\mathscr{C}/\sim[/ilmath] where:[1]
- [ilmath]\mathscr{C} [/ilmath] - the set of all Cauchy sequences in [ilmath]\mathbb{Q} [/ilmath] - the quotients
- [ilmath]\sim[/ilmath] - the usual equivalence of Cauchy sequences
We further claim:
- that the familiar operations of addition, multiplication and division are well defined and
- by associating [ilmath]x\in\mathcal{Q} [/ilmath] with the sequence [ilmath] ({ x_n })_{ n = 1 }^{ \infty }\subseteq \mathbb{Q} [/ilmath] where [ilmath]\forall n\in\mathbb{N}[x_n:=x][/ilmath] we can embed [ilmath]\mathbb{Q} [/ilmath] in [ilmath]\mathbb{R}:=\mathscr{C}/\sim[/ilmath]
