I need help with this question. It says to use Corollary 5.10(meaning this: A finite set is not equivalent to any of its proper subsets) to show that the rationals Q are infinite.

How would I go about doing this?

Thanks for your help!

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- April 25th 2008, 07:34 PMcalcprincess88Help with a proof please!
I need help with this question. It says to use Corollary 5.10(meaning this: A finite set is not equivalent to any of its proper subsets) to show that the rationals Q are infinite.

How would I go about doing this?

Thanks for your help! - April 25th 2008, 09:46 PMTheEmptySet
Lets rewrite the Corollary as an if then statement

If a Set is finite then it is not equivelent to any of its proper subsets

Use the contrapositive of this corollary.

if a set is equivelent to any of its proper subsets, then the set is infinite

See what you can do from here.

Good luck. - April 25th 2008, 10:59 PMIsomorphismQuote:

If a set is equivelent to any of its proper subsets, then the set is infinite

- April 27th 2008, 12:07 PMcalcprincess88
Thanks for your help! I'll try to do it and see what I can come up with and if I need anymore help I'll come back! Thanks again!