| Exam Board | OCR |
|---|---|
| Module | H240/01 (Pure Mathematics) |
| Year | 2017 |
| Session | Specimen |
| Marks | 3 |
| Topic | Proof |
| Type | Existence of greatest/smallest element |
| Difficulty | Moderate -0.5 This is a straightforward proof by contradiction requiring students to assume a greatest even integer exists, then show 2n+2 is larger, creating a contradiction. The logic is simple and the technique is standard, making it easier than average, though it does require understanding proof structure rather than just calculation. |
| Spec | 1.01d Proof by contradiction |
Prove by contradiction that there is no greatest even positive integer.
[3]
\hfill \mbox{\textit{OCR H240/01 2017 Q6 [3]}}