TMUA-P2-PRF2-009 — Paper P2 · Proof by cases · Level 2

Options

1. A
   $x=2$ only.
2. B
   $x=-1$ only.
3. C
   $x=2$ or $x=-1$; the cases $2x-1 \ge 0$ and $2x-1<0$ give $2x-1=3$ and $2x-1=-3$.
4. D
   $x=1$ or $x=-2$.

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

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