How Are Monotone Sequence Conditions and Least Upper Bound Property Equivalent?

  • Thread starter Thread starter Scousergirl
  • Start date Start date
  • Tags Tags
    Condition Sequence
Scousergirl
Messages
15
Reaction score
0
Prove that the monotone sequence condition is equivalent to the least upper bound theory.

I can't seem to get around how to prove that the two are equivalent. (it seems trivial).
 
Physics news on Phys.org
Suppose you start from the monotone sequence condition. Given a bounded set, can you somehow use its upper bounds in some sort of useful sequence? Think of how the monotone sequence condition could apply here.

On the other hand, suppose we have the least upper bound property. Given a monotone sequence (say, a non-decreasing one) that's bounded above, is there a natural way we can transform this sequence into a bounded set? What relation could such a set's upper bound have to our sequence?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top