# Vertical alignment of an array with numbered list

by Subhajit Paul   Last Updated July 12, 2019 11:23 AM - source

please refer to the following scenarios: and The first case is generated by the following part of the script:

\question[5+2]
Let $(X,d)$ be a metric space and $A\subseteq X$. \textit{Boundary} of $A$ is defined as $\partial A=\bar{A}\setminus A^{\circ}$. Show that,
\begin{parts}
%3.a.
\part
$\begin{array}{rcl} \partial A &=& (A^{\circ}\cup \ext A)^{c}\\[1ex] &=& \{x\in X:\forall\d>0, N_{\d}(x)\cap A\ne\emptyset\text{ and }N_{\d}(x)\cap A^{c}\ne\emptyset\}. \end{array} \tag*{\parbox{1pt}{\droppoints}}$


and the second instance is generated by

\question[5+2]
Let $(X,d)$ be a metric space and $A\subseteq X$. \textit{Boundary} of $A$ is defined as $\partial A=\bar{A}\setminus A^{\circ}$. Show that,
\begin{parts}
%3.a.
\part
$\begin{array}{rcl} \partial A &=& (A^{\circ}\cup \ext A)^{c}\\[1ex] &=& \{x\in X:\forall\d>0, N_{\d}(x)\cap A\ne\emptyset\text{ and }N_{\d}(x)\cap A^{c}\ne\emptyset\}. \end{array}$\droppoints


What I want is to align the first line of the array with the question number (a). How can I achieve that?

I am using exam class. Here is my preamble.

\documentclass[a5paper,11pt]{exam}
\usepackage[left=0.25in,right=0.75in,top=0.5in,bottom=0.5in,footskip=.15in]{geometry}
\usepackage{amsmath, amssymb, amsthm, amsfonts}
\usepackage[english]{babel}
\usepackage{mathtools}
\usepackage[inline]{enumitem}
\usepackage{mathrsfs}
\usepackage{nccmath}
\usepackage{stmaryrd}
\usepackage{mathdots}
\usepackage{lastpage,refcount}
\footer{}{\small\thepage}{\ifodd\value{page}\relax
\if\thepage\getpagerefnumber{LastPage}\relax
\else \tiny {\mbox{\kern\dimexpr+4.75in\relax}}\boxed{\textbf{Turn Over}}
\fi
\fi}
\usepackage{etoolbox}
\makeatletter
\setlength\@rightmargin{0.5in}
\patchcmd\[email protected]@toks{\llap{\[email protected]@block}}{\rlap{\[email protected]@block}}{}{}
\patchcmd\droppoints{\llap{\[email protected]@block}}{\rlap{\[email protected]@block}}{}{}
\patchcmd\droptotalpoints{\llap{\[email protected]}}{\rlap{\[email protected]}}{}{}
\patchcmd\droptotalbonuspoints{\llap{\[email protected]}}{\rlap{\[email protected]}}{}{}
\makeatother

\marksnotpoints
\bracketedpoints
\pointsdroppedatright

\renewcommand\partlabel{(\textbf{\alph{partno}})}
\renewcommand{\thesubpart}{(\textit{\roman{subpart}})}
\renewcommand{\subpartlabel}{\thesubpart}
\renewcommand\questionlabel{\textbf{\thequestion.}}

\newcommand{\R}{\mathbb{R}}
\newcommand{\N}{\mathbb{N}}
\newcommand{\Q}{\mathbb{Q}}
\newcommand{\Z}{\mathbb{Z}}
\renewcommand{\a}{\alpha}
\renewcommand{\b}{\beta}
\newcommand{\g}{\gamma}
\renewcommand{\d}{\delta}
\newcommand{\e}{\epsilon}
\DeclareMathOperator{\interior}{int}
\DeclareMathOperator{\ext}{ext}
\newcommand{\abs}{\left\lvert #1 \right\rvert}
\newcommand{\norm}{\left\lVert #1 \right\rVert}

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