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%This is a comment, because it follows a percent symbol on a line.
%If you precede every line from here to the end with a % , then \TeX\ will
%process nothing at all and so this document should SURELY compile correctly!
%But let's leave these lines in here to put TeX through its paces!
\centerline{ Typing in \TeX\ is easy. }
\bigskip
An empty line tells \TeX\ to start a new paragraph. Commendable hyphenation
algorithms automatically facilitate beautification incessantly thereafter,
unencumbered whenever tremendously sesquipedalian verbiage necessitates
linebreaking, lexicographic hooliganism (``goofywordcreationitis") notwithstanding!
Short-hyphens, the dashes used Jan -- Apr, and the longer dashes --- notice
the differences! --- are easy to produce; there are also minus signs:
$3-4=-1$.
Check out the ligatures in find, flex, giraffe, waffle, and quaffing!
And \AE sop's Curriculum Vit\ae\ (C.~V.) shows N\o rsk \oe uvres!
We can get accented ch\~a\^r\"a\c ct\.e\`r\'s and matched
``quotation'' marks (``marks").
Greek letters are easy, even in capitals, and in
variations: $\Gamma_\Gamma = (\epsilon+\varepsilon)(\phi+\varphi)$.
\font\tenrm=cmr10 \font\ninerm=cmr9 \font\eightrm=cmr8 \font\sevenrm=cmr7
All the {\it font} {\sl tricks} you {\bf need} --- and {\tt some}
you {\tenrm really \ninerm really \eightrm really \sevenrm really} don't.
Equations can be in-line, like $2+2=4,$ or displayed, like $$2+2=4,$$
and can use symbols galore: \TeX, \ss, \dag, \ddag, \P, \S, $\cal A, G$,
$\Rightarrow$, $\iff$, $\forall$, $\emptyset$, $\in$, $\cup,\cap$, $\subseteq$,
$\hbar$, $\nabla$, $\angle$, $\times$, $\div$, $\pm$, $\infty$, $\aleph$,
$\int$, $\oint$, $\partial$, $\Re$, $\triangle$, $\approx$, $98.6^\circ$,
$\sharp$, $\clubsuit$.
\TeX\ is clever about context: Notice how it treats in-line formulas
$\lim_{x\to 0} { {\cos(x)} \over x }$
differently from displayed ones:
$$\lim_{x\to 0} { {\cos(x)} \over x }$$
and distinguishes text ($\lim$) from math letters ($lim$);
observe that \TeX\ understands that ``subscripting" differs for sigmas
and for sums:
$$ \Sigma_{i=1}^n a_i \qquad \hbox{versus} \qquad \sum_{i=1}^n a_i $$
Symbols piece together correctly:
$\sqrt{\bigcup X_{\lambda}}= \int_1^2 x^3 dx$,
$a^{a^{a^a}}$,
${}^{92}U_{238}^{+}$ (or should that be $U_{238^{+}}$?)
(and note that $3!\not=3$ !). Compare ${ 3\over 2 } $ to $3/2 $
and note the ease with which we get tall symbols, and arrays:
$$ \left( {1\over{1+{1\over{1+{1\over{1+1}}}}}} \right)
\qquad\hbox{ and }\qquad
\matrix{ \hbox{May} & 2 & 3 &4 \cr 5 & film & \hbox{ film }
& \pmatrix{\xi &2\cr 3&4\cr} \cr} $$
For really hard stuff just leave a big space;
\vspace{1.2 in}
it's OK by me to draw in figures by hand.
Don't forget to include the correct line to end your documents$\ldots$
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