TMUA-P2-ERR2-001 — Paper P2 · Common fallacies · Level 1

Options

1. A
   It fails when $a = 0$: e.g. $0 \times 2 = 0 \times 7$ but $2 \ne 7$.
2. B
   It fails when $b = c = 0$.
3. C
   It fails only for fractions.
4. D
   It fails when $a$, $b$, $c$ are all positive.
5. E
   It never fails; cancelling $a$ is always legal.

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

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