LaTeX Forum

\documentclass[a4paper,11pt]{report}
\usepackage{amsmath}

\begin{document}

\begin{itemize}        
  \item \begin{equation*}
          \begin{split}
             P_{2r} &= \{A \rightarrow 1, A \rightarrow 1A, A \rightarrow 0A, S \rightarrow 1A, B \rightarrow 1A, C \rightarrow 0A, \\
                    & \quad S \rightarrow 0B, C \rightarrow 0B, S \rightarrow 0C\} \\
             \delta &= \{(A,1,f), (A,1,A), (A,0,A), (S,1,f), (S,0,B), (S,0,C), \\
                    & \quad (B,1,A), (C,0,A), (C,0,B)\}
          \end{split}
        \end{equation*}
\end{itemize}

\end{document}

\documentclass[11pt,a4paper]{scrartcl}
\usepackage[T1]{fontenc}
\usepackage{mathtools}  % lädt »amsmath«

\begin{document}
  \begin{itemize}
    \item \(
            \begin{aligned}[t]
              P_{2r} &= \{A \to 1, A \to 1A, A \to 0A, S \to 1A, B \to 1A, C \to 0A, \\
                     &  \;\quad S \to 0B, C \to 0B, S \to 0C\} \\
              \delta &= \{(A,1,f), (A,1,A), (A,0,A), (S,1,f), (S,0,B), (S,0,C), \\
                     &  \;\quad (B,1,A), (C,0,A), (C,0,B)\}
            \end{aligned}
          \)
  \end{itemize}
\end{document}