TMUA-P2-PRF2-004 — Paper P2 · Proof by cases · Level 2

Options

1. A
   $x = 1$, $x = -1$ only.
2. B
   $x$ rational and $x$ irrational.
3. C
   $x > 0$ and $x < 0$.
4. D
   $x > 1$ and $x < -1$.
5. E
   $x < -1$, $-1 \le x \le 1$, and $x > 1$.

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

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