domain, then the preimage under $f$ of $A$ is $\preimage{f}{A}$.
\end{section}
+ \begin{section}{Calculus}
+ The gradient of $f : \Rn \rightarrow \Rn[1]$ is $\gradient{f} :
+ \Rn \rightarrow \Rn$.
+ \end{section}
+
\begin{section}{Common}
The function $f$ applied to $x$ is $f\of{x}$. We can group terms
like $a + \qty{b - c}$ or $a + \qty{b - \sqty{c - d}}$. Here's a
\begin{equation*}
\unionmany{k=1}{\infty}{A_{k}} = \intersectmany{k=1}{\infty}{B_{k}}
\end{equation*}
+
+ Finally, we have the four standard types of intervals in $\Rn[1]$,
+ %
+ \begin{align*}
+ \intervaloo{a}{b} &= \setc{ x \in \Rn[1]}{ a < x < b },\\
+ \intervaloc{a}{b} &= \setc{ x \in \Rn[1]}{ a < x \le b },\\
+ \intervalco{a}{b} &= \setc{ x \in \Rn[1]}{ a \le x < b }, \text{ and }\\
+ \intervalcc{a}{b} &= \setc{ x \in \Rn[1]}{ a \le x \le b }.
+ \end{align*}
+ \end{section}
+
+ \begin{section}{Complex}
+ We sometimes want to conjugate complex numbers like
+ $\compconj{a+bi} = a - bi$.
\end{section}
\begin{section}{Cone}
The conic hull of a set $X$ is $\cone{X}$; its affine hull is
$\aff{X}$, and its convex hull is $\conv{X}$. If $K$ is a cone,
then its lineality space is $\linspace{K}$, its lineality is
- $\lin{K}$, and its extreme directions are $\Ext{K}$.
+ $\lin{K}$, and its extreme directions are $\Ext{K}$. The fact that
+ $F$ is a face of $K$ is denoted by $F \faceof K$; if $F$ is a
+ proper face, then we write $F \properfaceof K$.
\end{section}
\begin{section}{Font}
their tensor product is $\tp{x}{y}$. The Kronecker product of
matrices $A$ and $B$ is $\kp{A}{B}$. The adjoint of the operator
$L$ is $\adjoint{L}$, or if it's a matrix, then its transpose is
- $\transpose{L}$. Its trace is $\trace{L}$.
+ $\transpose{L}$. Its trace is $\trace{L}$. Another matrix-specific
+ concept is the Moore-Penrose pseudoinverse of $L$, denoted by
+ $\pseudoinverse{L}$.
The span of a set $X$ is $\spanof{X}$, and its codimension is
$\codim{X}$. The projection of $X$ onto $V$ is $\proj{V}{X}$. The
fox
\end{theorem}
+ \begin{exercise}
+ jumps
+ \end{exercise}
+
\begin{definition}
quod
\end{definition}
fox
\end{theorem*}
+ \begin{exercise*}
+ jumps
+ \end{exercise*}
+
\begin{definition*}
quod
\end{definition*}