TMUA-P2Z-PRF3-001 — Paper P2 · Proof by contradiction · Level 1

Options

1. A
   Assume there are infinitely many primes.
2. B
   Assume only finitely many primes exist, so there is a largest prime $P$ (a complete list $p_1, \dots, p_k$ with $P$ biggest).
3. C
   Assume $2$ is the largest prime.
4. D
   Assume every integer is prime.
5. E
   Assume nothing; exhibit a prime larger than any given integer directly.

Letters only — the answer key is hidden. Work it out, then check the solution below.

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