#LyX 2.3 created this file. For more info see http://www.lyx.org/
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subequations
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\begin_body

\begin_layout Standard
The 
\family typewriter
subequations
\family default
 environment is provided in LyX by the 
\family typewriter
subequations
\family default
 module (Document > Settings > Modules).
 It is helpful to group logically-linked equations.
 For example, the one-speed one-dimensional integro-differential equation
 with 
\begin_inset Formula $0\le x\le X$
\end_inset

 and 
\begin_inset Formula $-1\le\mu\le1$
\end_inset

 shown in Eq.
\begin_inset space ~
\end_inset


\begin_inset CommandInset ref
LatexCommand ref
reference "eq:odoglbe"

\end_inset

 has associated boundary conditions shown in Eqs.
\begin_inset space ~
\end_inset


\begin_inset CommandInset ref
LatexCommand ref
reference "eq:rlbc"

\end_inset

 and 
\begin_inset CommandInset ref
LatexCommand ref
reference "eq:vrbc"

\end_inset

.
\begin_inset Flex Subequations
status open

\begin_layout Plain Layout
\begin_inset Formula 
\begin{align}
\mu\frac{d\psi\left(x,\mu\right)}{dx}+\Sigma_{t}\left(x\right)\psi\left(x,\mu\right) & =\intop_{-1}^{1}\frac{\Sigma_{s}\left(x,\mu'\to\mu\right)}{2}\psi\left(x,\mu'\right)d\mu'+\frac{Q\left(x,\mu\right)}{2},\label{eq:odoglbe}\\
\psi\left(0,\mu\right) & =\psi\left(0,-\mu\right)\,,\,0<\mu\le1,\label{eq:rlbc}\\
\psi\left(X,\mu\right) & =0\,,\,-1\le\mu<0.\label{eq:vrbc}
\end{align}

\end_inset


\begin_inset CommandInset label
LatexCommand label
name "eq:odoglbeset_aligned"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Standard
In the previous case, the equations use the 
\family typewriter
amsmath
\family default
 
\family typewriter
align
\family default
 environment; however, this is not necessary as shown in Eqs.
\begin_inset space ~
\end_inset


\begin_inset CommandInset ref
LatexCommand ref
reference "eq:odoglbenoa"

\end_inset

–
\begin_inset CommandInset ref
LatexCommand ref
reference "eq:vrbcnoa"

\end_inset

.
 
\begin_inset Flex Subequations
status open

\begin_layout Plain Layout
\begin_inset Formula 
\begin{equation}
\mu\frac{d\psi\left(x,\mu\right)}{dx}+\Sigma_{t}\left(x\right)\psi\left(x,\mu\right)=\intop_{-1}^{1}\frac{\Sigma_{s}\left(x,\mu'\to\mu\right)}{2}\psi\left(x,\mu'\right)d\mu'+\frac{Q\left(x,\mu\right)}{2},\label{eq:odoglbenoa}
\end{equation}

\end_inset


\begin_inset Formula 
\begin{equation}
\psi\left(0,\mu\right)=\psi\left(0,-\mu\right)\,,\,0<\mu\le1,\label{eq:rlbcnoa}
\end{equation}

\end_inset


\begin_inset CommandInset label
LatexCommand label
name "eq:odoglbeset_individual"

\end_inset


\begin_inset Formula 
\begin{equation}
\psi\left(X,\mu\right)=0\,,\,-1\le\mu<0.\label{eq:vrbcnoa}
\end{equation}

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Standard
As an alternative to cross-referencing each subequation directly, the group
 of subequations (i.e., Eq.
\begin_inset space ~
\end_inset


\begin_inset CommandInset ref
LatexCommand ref
reference "eq:odoglbeset_aligned"

\end_inset

 and/or Eq.
\begin_inset space ~
\end_inset


\begin_inset CommandInset ref
LatexCommand ref
reference "eq:odoglbeset_individual"

\end_inset

) can be referenced by placing a label within the subequation inset but
 outside the equation(s).
\end_layout

\end_body
\end_document