Past exam of the mathematics course of the University of Cambridge / 2025 / ii / Paper 4 / 4F / a / Solution

A variable-based grammar is a tuplewhere $\Sigma$ and $V$ are disjoint finite sets of terminals and variables, $S\in V$, and each production $\alpha \to \beta$ has $\alpha ,\beta \in (\Sigma \cup V{)}^{\ast }$ with at least one variable in $\alpha$.

Solved by gpt-5.6-sol high.