Math Is Fun Forum

shocamefromebay

Member

Registered: 2007-05-30

Posts: 103

Bijection between an open and half closed interval?

I'm doing this math puzzle sheet that my teacher has given me for fun to prep for the putnam, and I can't quite figure this one out. It's supposedly one of the easier questions, but it still hurts my head.

It wants me to find a bijection h: (0,1)->[1,3).

Any ideas?

Last edited by shocamefromebay (2011-10-04 01:29:47)

Bob

Administrator

Registered: 2010-06-20

Posts: 10,623

Re: Bijection between an open and half closed interval?

hi shocamefromebay

Got this by adapting the idea from

http://mathforum.org/library/drmath/view/62858.html

Then, define h(x) as follows:

Bob

Last edited by Bob (2011-10-04 05:58:23)

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