# How to Combine Bijections to get all real integers to A or B watch

1. if f: Z+ > A and g: Z+ > B
how do you show that you can combine them to get h: Z+ > AUB?
Given that f and g are bijections?

Very stuck :/
2. Hint: can you find two copies of Z+ inside Z+?
3. (Original post by around)
Hint: can you find two copies of Z+ inside Z+?
Two copies?
4. (Original post by EllieLC)
Two copies?
Well, if you could find two copies of Z+ inside Z+, you could map one to A using f, and one to B using g.

So Z+ = {0, 1, 2, 3, ...}. Can you divide this set into two?

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