Mathematics: Analysis and Approaches · Topic 1: Number and algebra

AHL1.15 — Proof: induction, contradiction and counterexample

Mathematics: Analysis and Approaches · SL / HL · syllabus-mapped notes

1. Proof by mathematical induction

   Base case, assume $P(k)$, then prove $P(k)\Rightarrow P(k+1)$.

2. Proof by contradiction

   Assume the statement is false and derive a contradiction.

3. Disproof by counterexample

   One explained example that breaks a universal claim.