Math CentralQuandaries & Queries


Question from Nazrul, a teacher:

How can I prove that the set of all positive odd integers is an infinite set.
Thank you in advance.


There are two ways that you could try.

One way is to put them into 1-1 correspondence with a known infinite set, say the positive integers. Another way is to suppose the set is finite, and therefore has a biggest element. Then find an odd positive integer bigger than that, a contradiction.

Good luck,

About Math Central


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.
Quandaries & Queries page Home page University of Regina PIMS