\listfiles
\documentclass{jarticle}
\usepackage{enumitem}
\usepackage{mathtools,amssymb}
\usepackage{listliketab}

\newcounter{listliketablabel}
\newcommand*{\nextnum}{\addtocounter{listliketablabel}{1}\thelistliketablabel)}
\makeatletter
\newcommand*{\storestyleofextra}[2][]{%
    \begin{lrbox}{\llt@list@box}
        \noindent
        \begin{minipage}{\linewidth}
            \begin{#2}[#1]
            \item[] \storeliststyle{}
            \end{#2}
        \end{minipage}
    \end{lrbox}\ignorespacesafterend
}
\makeatother
\storestyleofextra[noitemsep,label=\alph*)]{enumerate}
\newenvironment{alignerate}{%
    \begin{listliketab}
        \setcounter{listliketablabel}{0}\renewcommand*{\thelistliketablabel}{\alph{listliketablabel}}
        \renewcommand*{\item}{\nextnum &}
    \begin{tabular}{L>{\(}r<{\)}@{}>{\({}}l<{\)}R}
}{
    \end{tabular}
    \end{listliketab}
}

\begin{document}

\begin{alignerate}
\item \nu(A \wedge B) 
& = \begin{cases*} 1, & if $\nu(A) = \nu(B) = 1$; \\
                   0, & otherwise.        
\end{cases*}       \\
\item \nu(A \vee B)   
& = \begin{cases*} 1, & if $\nu(A) = 1$ or $\nu(B) = 1$; \\
                      0, & otherwise.
\end{cases*}\\
\item \nu(A \rightarrow B) 
& = \begin{cases*} 1, & if $\nu(A) = 0$ or $\nu(B) = 1$; \\
    0, & otherwise.
\end{cases*}
\end{alignerate}

\end{document}
