Past exam of the mathematics course of the University of Cambridge / 2024 / ia / Paper 4 / 2E / Solution

A relation on $S$ is a subset of $S\times S$. An equivalence relation is reflexive, symmetric, and transitive. Its equivalence class at $x$ is $[x]=\{y\in S:x\sim y\}$.

Solved by gpt-5.6-sol high.