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Here is my masterpiece. Spacing     is   totally irrelevant.  Words will all get pushed together    correctly.
Here is a new sentence.

Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph. Here is a new paragraph.

Typing words is as usual.

All math goes in dollar signs like this.  Here is $\sqrt{2}$. Here is an integral $\int_a^b \hat{f}(x) dx$. Here is a summation $\sum_i=1^n a_i$ or $\sum_{i=1}^n a_i.$ If I want a centred equation, I can use double dollar signs like this
$$ \int_a^b \hat{f}(x) dx$$
or like this
$$\sum_{i=1}^n a_i.$$
Suppose that I want to type a matrix. Here it goes
$$
A = 
\begin{matrix}
a &b &c \\
d &e &f \\
g &h &i \\
\end{matrix}
$$


$$
A = 
\begin{bmatrix}
a &b &c \\
d &e &f \\
g &h &i \\
\end{bmatrix}
$$

$$
A = 
\begin{pmatrix}
a &b &c \\
d &e &f \\
g &h &i \\
\end{pmatrix}
$$

Suppose that we want to typeset a dollar sign. What do we do?  Here is \$10. What about other symbols. Math \& Stats There are several others.
\# \% \_ \{ \} 

We use a double backslash to end a line.\\

Here it is. To type a slash, we use \slash But a forward slash is not a problem / like this. Let's try $\backslash$.
 
The squiggle (or tilde) gives a nonbreaking space like this. Here is equation~1.2 which says something wonderful. The problem is, suppose that we wnat to give a web address like this
\begin{center}
http://stat.math.uregina.ca/~kozdron
\end{center}
\begin{center}
http://stat.math.uregina.ca/$\sim$kozdron
\end{center}

Suppose we want to change font syles. Here is some \textbf{bold}, or some \emph{italics}, or some \textsc{small caps}, or some \texttt{typewritten} text.

\begin{center}
\texttt{http://stat.math.uregina.ca/$\sim$kozdron}
\end{center}

$a \leq b \cong c \propto d$

We also use a lot of Greek letters in math. $\alpha$ $\beta$ $\theta$ $\phi$ $\rho$ $\sigma$ $\epsilon$ You can also use $\varphi$ or $\vartheta$ or $\varrho$ or $\varsigma$ or $\varepsilon$. For capital letters, we just use $\Sigma$ or $\Theta$ $\Gamma$ $\Delta$ Suppose I want to type a Hungarian name with accents like this H\'{a}j\`{e}k\v{s}

$a \pm b$ or $a \div b$ or $a \ast b$ or $a\oplus b$

$\left\lfloor a \right \rfloor$

$$\prod_{i=1}^n a_i$$
 
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