Past exam of the mathematics course of the University of Cambridge / 2023 / ii / Paper 3 / 4I / c / Solution

Two formal grammars over the same terminal alphabet are isomorphic when there is a bijection $\varphi :V_0\to V_1$ between their nonterminals such that $\varphi (S_0)=S_1$ andwhere $\varphi$ is extended to words by fixing each terminal and acting symbol by symbol.

Solved by gpt-5.6-sol high.