\begin{frame}
  \frametitle{Exercise: For All \& Implication}
    
  \begin{goal}{}
    \begin{salign}
      \forall\,X\,(\varphi_1 \Rightarrow \varphi_2)
      \;\;\equiv\;\; &\neg\exists\,X\,(\varphi_1 \wedge \neg\varphi_2) 
    \end{salign}
  \end{goal}
  \medskip
  
  The formula
  \logicquerya
  \pause  
  is \emph{logically equivalent to}
  \logicqueryb
\end{frame}