Vectors in LaTeX
A vector is a quantity with direction and magnitude; in LaTeX it is marked with \vec (a small arrow), with bold type via \mathbf, or written out as a column with a one-column matrix.
LaTeX command
\vec{v}Not the symbol you meant? Draw it to find the command →
The direct command is \vec{v}, which draws a short arrow over a single symbol. Physics and engineering texts often prefer bold instead, using \mathbf{v} for an upright bold letter. Pure mathematics frequently uses no decoration at all and relies on context. Pick one convention and keep it consistent throughout a document.
A column vector is just a one-column matrix, so \begin{pmatrix} x \\ y \\ z \end{pmatrix} stacks the components. Row vectors use a single row with & between entries. For the displacement from A to B use \overrightarrow{AB}, and for a unit vector use a hat, as in \hat{\mathbf{n}} or \hat{\imath}.
Operations read naturally: \mathbf{a} \cdot \mathbf{b} is the dot (scalar) product and \mathbf{a} \times \mathbf{b} is the cross product. Note that \mathbf bolds Latin letters and uppercase Greek but not lowercase Greek; to bold a lowercase Greek symbol you need \boldsymbol, and the column-vector matrix environments require amsmath.
Other forms
\mathbf{v}bold vector\begin{pmatrix} x \\ y \\ z \end{pmatrix}a column vectorExamples
$\vec{v} = \begin{pmatrix} 1 \\ 2 \\ 3 \end{pmatrix}$an arrow-marked column vector
$\mathbf{a} \cdot \mathbf{b}$a dot (scalar) product in bold notation
$\mathbf{a} \times \mathbf{b}$a cross product
$\hat{\imath} + 2\hat{\jmath} - \hat{k}$unit vectors with hats (\imath has no dot)
$\overrightarrow{AB} = \vec{b} - \vec{a}$the displacement from A to B
Tips and common mistakes
\vec{v}draws a small arrow over one symbol only; for several symbols use\overrightarrow{AB}.\mathbfgives an upright bold Latin letter but will not bold lowercase Greek; use\boldsymbol{\omega}for a bold Greek vector.- Write a column vector as a single-column pmatrix and a row vector as a single-row one; both need amsmath.
- For unit vectors,
\hat{\imath}and\hat{\jmath}use dotless letters so the hat sits cleanly. - Do not mix arrow and bold notation in one document; choose a single convention and apply it everywhere.
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Convert your maths to LaTeX →FAQ
How do I put an arrow over a vector in LaTeX?
Use \vec{v} for a single symbol. For a labelled segment spanning two letters, use \overrightarrow{AB}, which stretches the arrow across both.
How do I write a column vector?
Use a one-column matrix: \begin{pmatrix} x \\ y \\ z \end{pmatrix}. The \\ ends each row so the components stack vertically.
How do I make a bold vector?
Use \mathbf{v} for a bold upright Latin letter. For a bold Greek letter such as omega, use \boldsymbol{\omega} instead, since \mathbf does not affect lowercase Greek.