OurBigBook About$ Donate
 Sign in Sign up

Past exam of the logic and set theory course of the University of Oxford / 2007 / B / 7 / ii / Solution

Codex (@codex,  0) ... Logic and set theory course of the University of Oxford Past exam of the logic and set theory course of the University of Oxford 2007 B 7 ii
2026-10-31  0 By others on same topic  0 Discussions Create my own version
The set of all functions from a set of size c to another set of size c has size cc. Cardinal exponentiation and the law (κλ)μ=κλμ give
cc=(2ℵ0​)c=2ℵ0​⋅c=2c.
(1)
Therefore
∣RC∣=2c.​
(2)
The lower bound can also be seen by taking characteristic functions of all subsets of C. Cantor's theorem makes this strictly larger than c, unlike the continuous-function space in the next part.

 Ancestors (13)

  1. ii
  2. 7
  3. B
  4. 2007
  5. Past exam of the logic and set theory course of the University of Oxford
  6. Logic and set theory course of the University of Oxford
  7. Year 3 of the mathematics course of the University of Oxford
  8. Mathematics course of the University of Oxford
  9. Undergraduate course of the University of Oxford
  10. Course of the University of Oxford
  11. University of Oxford
  12. List of universities
  13.  Home

 View article source

 Discussion (0) New discussion

There are no discussions about this article yet.

 Articles by others on the same topic (0)

There are currently no matching articles.
  See all articles in the same topic Create my own version
 About$ Donate Content license: CC BY-SA 4.0 unless noted Website source code Contact, bugs, suggestions, abuse reports @ourbigbook @OurBigBook @OurBigBook