# Mis-alignment in itemize environment

I'm getting an unexpected left-alignment result with what I think is a simple itemize environment -- haven't had any issues like this before. Here is the code:

\begin{itemize}
\item[(i)] Some text; \vspace{4pt}

\item[(ii)] Some text \vspace{4pt}

\item[(iii)]If $B_1, B_2 \in \mathfrak{B}(\mathbb{R})$ with $(B_1 \cap B_2) = \emptyset$, then\\ \vspace{3pt}
\hspace{2cm} $P_X(B_1 \cup B_2) = P_X(B_1) + P_X(B_2)$:\\ \vspace{3pt}
Since $B_1$ and $B_2$ are disjoint their pre-images in $\Omega$ will be disjoint and by the
$\sigma$-additivity of $P$ on $\mathcal{A}$ we have that,\\ \vspace{3pt}
$P(X^{-1}(B_1 \cup B_2)) = P(X^{-1}(B_1)) + P(X^{-1}(B_2))\\ \vspace{3pt} \hspace{2cm} = P_X(B_1) + P_X(B_2)$. \\
\end{itemize}


The problem is with the third item. When the text beginning Since' (following the line break) wraps it appears to align to the left of the start of the rest of the elements. I don't think the problem is with the line break because that has note caused issues before for me. Any ideas?

Perhaps you want to use display math. I see no reason for so many \vspace instructions. Let TeX do the alignments.

\documentclass{article}
\usepackage{amsmath,amssymb}

\begin{document}

\begin{itemize}
\item[(i)] Some text;

\item[(ii)] Some text

\item[(iii)] If $B_1, B_2 \in \mathfrak{B}(\mathbb{R})$ with
$(B_1 \cap B_2) = \emptyset$, then
$P_X(B_1 \cup B_2) = P_X(B_1) + P_X(B_2)$
Since $B_1$ and $B_2$ are disjoint their pre-images in $\Omega$ will be disjoint
and by the $\sigma$-additivity of $P$ on $\mathcal{A}$ we have that
\begin{align*}
P(X^{-1}(B_1 \cup B_2)) &= P(X^{-1}(B_1)) + P(X^{-1}(B_2))\\
&= P_X(B_1) + P_X(B_2).
\end{align*}
\end{itemize}

\end{document}


You can also use enumitem in order to avoid manual numbering.

\documentclass{article}
\usepackage{amsmath,amssymb}
\usepackage{enumitem}

\begin{document}

\begin{enumerate}[label=(\roman*)]
\item Some text;

\item Some text

\item If $B_1, B_2 \in \mathfrak{B}(\mathbb{R})$ with
$(B_1 \cap B_2) = \emptyset$, then
$P_X(B_1 \cup B_2) = P_X(B_1) + P_X(B_2)$
Since $B_1$ and $B_2$ are disjoint their pre-images in $\Omega$ will be disjoint
and by the $\sigma$-additivity of $P$ on $\mathcal{A}$ we have that
\begin{align*}
P(X^{-1}(B_1 \cup B_2)) &= P(X^{-1}(B_1)) + P(X^{-1}(B_2))\\
&= P_X(B_1) + P_X(B_2).
\end{align*}
\end{enumerate}

\end{document}

• Thanks. That solves the problem. The \vspace(s) are to compensate for poor eyesight. TeX's spacing is okay (for me) for regular text, but I find it difficult to read when math is involved. AMD is a real pain in the butt ... Jul 14 at 18:07
• I should have noted in my comment that items (i) and (ii) are all math in my document, but since they were not the problem I opted to put plain text in them for the purpose of the question. Jul 14 at 18:24
• @TonyK \linespread{1.2}` in the preamble would space out lines. Jul 14 at 19:49
• Well that's just nifty. Thank you Jul 15 at 5:23