TMUA-P2-PRF5-001 — Paper P2 · Following proofs · Level 1

Options

1. A
   That $j + k$ is odd.
2. B
   That $m + n$ is written as $2$ times an integer, which is exactly the definition of even.
3. C
   That every integer is even.
4. D
   That $m$ and $n$ are odd.
5. E
   Nothing; line (2) is unjustified.

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

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