WJEC Maths for A2 – Pure

9 Introduction You came across proofs in Topic 1 of the AS Pure Unit 1 course. A mathematical proof is a mathematical argument that convinces others that a mathematical statement is true. In this topic you come across one more technique to prove or disprove mathematical statements. This topic is concerned with a mathematical proof called proof by contradiction. As with all proofs, proof by contradiction depends on precise use of English as well as mathematical techniques. This topic covers the following: 1.1 Real, imaginary, rational and irrational numbers 1.2 Proof by contradiction 1.3 Proof of the irrationality of √ 2 1.4 Proof of the infinity of primes 1.5 Application of proof by contradiction to unfamiliar proofs