Proof

How mathematicians know that something is true for every case, not just the ones they have tried. Proof runs through the whole A Level, and questions may ask you to prove a result in any topic.

• An Overview — the structure of a proof, the notation and logical connectives, and the common mistakes

The content statements

• Proof by Deduction and Exhaustion — algebraic proofs about odd, even and consecutive integers; proof by checking every case
• Disproof by Counter-example — showing a statement is false with a single case where it fails

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Each page has step-by-step notes, several worked examples, a quick-reference grid and ten practice questions with fully worked solutions.