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courtrigrad
Jan2-05, 12:50 PM
Hello all

I need help with the following proofs

1. If x and y are arbitrary real numbers, prove that there is at least one real z satisfying x < z < y. (Do I just use the Archimedian Property?)

Thanks

hypermorphism
Jan2-05, 12:59 PM
(Do I just use the Archimedian Property?)


Yep. :smile:

matt grime
Jan2-05, 01:02 PM
No. and it isn't true as stated.

x and y must be distinct, and the requirement of being R is unnecessary, since it is true for Q (and C).


what is (x+y)/2?

hypermorphism
Jan2-05, 01:08 PM
Good catch. I was thinking of rational numbers between arbitrary reals.