\item \ifassignmentsheet \points{5} \fi
  Use the lazy encoding approach to check whether the formula $\varphi$ in $\EUF$ is satisfiable.
  \begin{align*}
	\varphi= 	& (\clause{(a=b); (a=f(a)); (b=f(a))}) \land (\clause{\lnot (a=b); (a=f(a))})~\land \\
		        & (\clause{\lnot (a=f(a)); (b=f(a))}) \land (\clause{(b=f(a)); (d=a)})~\land \\
		        & (\clause{\lnot (b=f(a)); (a=f(a))}) \land (\clause{\lnot (d=a); \lnot (a=f(a))})
  \end{align*}