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

Options

1. A
   Assume nothing; derive $\sqrt{2} = \frac{a}{b}$ from scratch.
2. B
   Assume $\sqrt{2} = 1.414$ exactly.
3. C
   Assume $\sqrt{2}$ is an integer.
4. D
   Assume $\sqrt{2}$ is rational, so $\sqrt{2} = \frac{a}{b}$ in lowest terms.
5. E
   Assume $\sqrt{2}$ is irrational.

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

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