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jmazurek
Jul21-04, 12:39 PM
Is the statement "Every bounded and monotone sequence of real numbers is convergent" proved my the monotone convergence theory? Thanks!!

AKG
Jul21-04, 04:05 PM
First of all, you mean theorem, not theory, I think. Seconf of all, what does this have to do with the convergence of a sequence of real numbers?:
http://mathworld.wolfram.com/MonotoneConvergenceTheorem.html

HallsofIvy
Jul22-04, 02:20 PM
Is the statement "Every bounded and monotone sequence of real numbers is convergent" proved my the monotone convergence theory? Thanks!!

?? That IS the "monotone convergence theorem".

One way to prove it is to define the real numbers as "equivalence classes of monotone sequences" where {an} is equivalent to {bn} if and only if {an-bn} converges to 0.

Another way is to define real numbers as Dedekind cuts which makes it easy to prove the "least upper bound" property and use that to prove the least upper bound theorem.

The "least upper bound property", "monotone convergenence", "Cauchy Criterion", "connectedness of the real numbers", and "every closed and bounded set is compact" are all equivalent- given any one you can prove the others. They are all "fundamental" in the sense that you can define the real numbers in ways that make it easy prove on or the other of these.