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In: Advanced Math

Suppose we had defined some bijection f : N → Q +. (a) Discuss how you...

Suppose we had defined some bijection f : N → Q +.

(a) Discuss how you could use f to prove that Q − is countably infinite. That is, define a new function h : N → Q − that uses f in some way. Discuss why using f makes h itself a bijection.

(b) Discuss how you could show that Q is countably infinite.

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