Questionnaire-2024/natural_deduction_propositional_logic/0017_sol.tex

\begin{logicproof}{2}
    \lnot \lnot p \land \lnot \lnot q & \prem \\
    r \land s & \prem \\
    \lnot \lnot p & $\ande{1} 1$ \\
    p & $\lnot \nege 3$ \\
    r & $\ande{1} 2$ \\
    s & $\ande{2} 2$ \\
    \lnot \lnot s & $\negnegi 6$ \\
    p \land r & $\andi 4,5$ \\
    (p \land r) \land \lnot \lnot s & $\andi 8,7$
\end{logicproof}