TMUA-P2-PRF2-014 — Paper P2 · Proof by cases · Level 3

Options

1. A
   $x=4$ only.
2. B
   $x=0$ or $x=4$; splitting at $1$ and $3$: for $x<1$ get $x=0$, for $1 \le x \le 3$ get $2=4$ (none), for $x>3$ get $x=4$.
3. C
   $x=1$ or $x=3$.
4. D
   Every $x$ in $[1,3]$.

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

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