Question: How do I represent the ordered pair representing a vector, without the usual open/close parentheses? My calculus textbook uses these:

![component of vector ](https://i.stack.imgur.com/Ji3l5.png)

Answer: 
```
\documentclass{article}
\usepackage{physics}
\usepackage{mathtools}
\DeclarePairedDelimiter{\opair}{\langle}{\rangle}
\begin{document}
  Using \verb|mathtools| and its \verb|DeclarePairedDelimiter| macro

  $\vb{a}=\opair{a,b}$

  Using \verb|physics| and its \verb|expval| macro

  $\vb{a}=\expval{a,b}$  or $\vb{a}=\ev{a,b}$
\end{document}

```

![enter image description here](https://i.stack.imgur.com/SLykb.png)
It looks like you're asking about form, not how to get the angle brackets, is that right?

I really don't like those angle brackets, because they tend to get used to mean other things (typically, the inner product).

Really, in my opinion, the best way to treat vectors is just like matrices (column or row vectors).

```
\mathbf{a} = \begin{bmatrix}a_x & a_y\end{bmatrix}'$

```

or

```
\mathbf{a} = \begin{bmatrix}a_x\\a_y\end{bmatrix}

```

Alternatively, you can use element (unit) vectors

```
\mathbf{a} = a_x \hat{x} + a_y \hat{y}.

```

There are many ways of writing the unit elements. The strictly mathy way is to use `$\mathbf{\mathup{e}}_x$`, or `$\hat\i$`.

I prefer the column vectors. That way, dot products work out nicely as `$\mathbf{a}'\mathbf{b}$`. For example, (noting that the prime indicates transposition)

![Output from example code.](https://i.stack.imgur.com/N3gu3.png)

Also, strictly speaking, the vectors should not be upright. They should be in bold italics. Upright symbols are reserved for mathematically defined quantities, such as pi, or e.