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Homework Statement
Show that R(x) cannot be made into a complete ordered field, where R(x) is the field of rational functions.
Homework Equations
Definition of a complete ordered field: An ordered field O is called complete if supS exists for every non empty subset S of O that is bounded above
The Attempt at a Solution
[tex]R(x)= \frac{P(X)}{Q(X)}
[/tex]
where P(X) and Q(X) are polynomials and Q(x) is not equal to 0.
I have proven in the past that Q (the rational numbers) is not a complete ordered field using the subset {y[tex]\in[/tex]R: y[tex]\geq[/tex]0 and [tex]y^{2} \leq[/tex]2}. Yet in the case of the rational functions as a field I am finding it very difficult.
I am fairly new to proofs (I switched from a non-proof based calc program to a honors proofed-base program) and I just don't know where to start. I understand the definition of a complete ordered field, a supremum and an infimum. I know that I have to prove in some way that a set of the rational functions is both bounded from above but can't have a supremum I just don't have a clue where I can start.
Please help me get started!