I've been reading through Goldblatt's book on the Hyperreals. And the star mapping is defined to be:
*r=[r]=[(r,r,r,...)]. Where r is a real number, and [r] denotes the equivalence class of the constant sequence r. It then goes on to say that the map r--> *r is an order preserving isomorphism from the Reals to the Hyperreals.
Question: How would one go about showing this though?