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Let $A \subseteq \mathbb{R}$ and $|A|=\omega$, prove $|\mathbb{R}\setminus A| = 2^\omega$.

Hint: $\mathbb{R}\sim \{0,1\}^\mathbb{N}$

I'm somewhat stuck trying to prove this, could someone give some hints (no full answers please)

I know $|A| = \omega < |\mathcal{P}(A)|=2^{\omega}$ (Cantor).

I guess I should look for some bijective function between $\mathbb{R}\setminus A$ and $\mathbb{R}$ or $\mathcal{P}(A)$. I also don't see how I can use the hint... Should I look for a bijection between $\mathbb{R}\setminus A$ and $\{0,1\}^\mathbb{N}$?

I was given another hint to use a diagonalization argument, but isn't that just usefull to prove strict equalities like $|A| < |\mathcal{P}(A)|$?

dietervdf
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    HINT: Search the site for at least two versions of this question. (You are correct about the diagonalization; it will only take you so far, but not further.) – Asaf Karagila May 17 '16 at 22:08
  • ADDITIONAL HINT: This is one question, which is in fact two, but there are more, http://math.stackexchange.com/questions/1310105/proving-mathbbr-mathbbs-2-aleph-0-when-mathbbs-subset-r-is-cou – Asaf Karagila May 17 '16 at 22:10
  • pfew, looks though. I'l look into the answers, thanks. (I'm not allowed to use AC) – dietervdf May 17 '16 at 22:26

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