Learn how to write the plus minus symbol (±) in LaTeX using the \pm command. This quick guide covers both plus-minus (±) and minus-plus (∓) symbols, with practical examples for equations, error margins, and mathematical notation.
To write the plus minus symbol (±) in LaTeX:
$\pm$ % Produces: ±Use \pm in math mode for plus-minus (±) and \mp for minus-plus (∓).
The \pm command produces the plus-minus symbol (±) in LaTeX. This symbol indicates that a value can be either added or subtracted, commonly used for error margins, tolerances, and approximate values.
% In inline math mode
The result is $5 \pm 2$.
% In display math mode
\[ x = 10 \pm 0.5 \]
% In equations
\begin{equation}
\mu = 100 \pm 5
\end{equation}Output:
The result is 5 ± 2.
x = 10 ± 0.5
Important: The \pm command only works in math mode. You must use it inside dollar signs $ $, display math \[ \], or equation environments.
The \mp command produces the minus-plus symbol (∓), which is the inverse of plus-minus. It's used when you need to indicate the opposite sign operation.
% Minus-plus symbol
The value is $8 \mp 3$.
% Combined with \pm for paired operations
\[ (a \pm b)(c \mp d) \]Output:
The value is 8 ∓ 3.
(a ± b)(c ∓ d)
When to use \mp: Use \mp when you want to indicate opposite signs, such as in algebraic expressions where one term adds while another subtracts: $(x \pm y)(x \mp y) = x^2 - y^2$
| Symbol | Command | Name | Meaning |
|---|---|---|---|
| ± | \pm |
Plus-Minus | Plus OR Minus (both possible) |
| ∓ | \mp |
Minus-Plus | Minus OR Plus (opposite of ±) |
The most common use of plus-minus is expressing measurement uncertainty:
% Scientific measurements
The temperature is $25.3 \pm 0.2$ degrees Celsius.
% Statistical data
The mean is $\mu = 50 \pm 3.5$ (95\% confidence interval).
% Physical constants
$g = 9.81 \pm 0.01$ m/s$^2$Quadratic equations and other formulas often have ± solutions:
% Quadratic formula
\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]
% Solutions to equations
The solutions are $x = 3 \pm \sqrt{5}$.
% Square root with both values
\[ \sqrt{4} = \pm 2 \]x = (-b ± √(b² - 4ac)) / 2a
√4 = ± 2
Engineering specifications often use plus-minus for acceptable ranges:
% Dimensional tolerances
Length: $100 \pm 0.5$ mm
% Voltage specifications
Operating voltage: $5.0 \pm 0.25$ V
% Resistance values
$R = 1000 \pm 50$ $\Omega$ (5\% tolerance)Using both symbols in algebraic expressions:
% Difference of squares
\[ (x \pm y)(x \mp y) = x^2 - y^2 \]
% Complex expressions
\[ (a \pm b)^2 = a^2 \pm 2ab + b^2 \]
% Trigonometric identities
\[ \sin(A \pm B) = \sin A \cos B \pm \cos A \sin B \]While \pm is designed for math mode, you can use it in regular text with these methods:
% Wrap in dollar signs
The tolerance is $\pm 5$\%.
% Multiple uses in text
The range is $\pm 10$ degrees with $\pm 2$\% accuracy.\usepackage{textcomp}
% In document
The temperature varies \textpm 3 degrees.% Works in both text and math mode
The value is \ensuremath{\pm} 5 units.Best Practice: Use inline math mode ($\pm$) for consistency with LaTeX's typesetting principles. It ensures proper spacing and compatibility across different contexts.
LaTeX automatically handles spacing around \pm as a binary operator, but you can adjust it:
% Default spacing (correct)
$x = 5 \pm 2$
% No extra spaces needed
$100 \pm 5$
% With units - use \, for thin space before unit
$25.3 \pm 0.2\,^{\circ}\text{C}$
% In fractions
$\frac{10 \pm 2}{5}$% With multiplication
$(5 \pm 1) \times (3 \pm 0.5)$
% With division
$\frac{100 \pm 5}{20 \pm 1}$
% With exponents
$(x \pm y)^2 = x^2 \pm 2xy + y^2$
% In subscripts/superscripts
$E_{\pm} = E_0 \pm \Delta E$% In fractions (automatically smaller)
$\frac{a \pm b}{c}$
% In subscripts (automatically smaller)
$x_{\pm}$
% In displaystyle (larger, more readable)
\[ \sum_{i=1}^{n} (x_i \pm \sigma_i) \]% WRONG - causes error
The value is \pm 5.
% CORRECT - use math mode
The value is $\pm 5$.% WRONG - extra spaces affect output
$ x = 5\pm2 $
% CORRECT - natural spacing
$x = 5 \pm 2$Remember: \pm produces ± (plus-minus) and \mp produces ∓ (minus-plus). They are not interchangeable! Use \mp only when you specifically need the opposite sign.
% WRONG - inconsistent units
$5 \pm 2$ meters and $3 \pm 500$ mm
% CORRECT - consistent units
$5.0 \pm 0.2$ m and $3.0 \pm 0.5$ m
% OR
$5000 \pm 200$ mm and $3000 \pm 500$ mm% Propagation of uncertainty
\begin{equation}
\Delta f = \sqrt{\left(\frac{\partial f}{\partial x}\Delta x\right)^2 + \left(\frac{\partial f}{\partial y}\Delta y\right)^2}
\end{equation}
% Multiple error sources
\[ R_{total} = R_1 \pm \delta R_1 + R_2 \pm \delta R_2 \]
% Matrix with tolerances
\[
\begin{pmatrix}
1.00 \pm 0.01 & 2.00 \pm 0.02 \\
3.00 \pm 0.03 & 4.00 \pm 0.04
\end{pmatrix}
\]% Mean and standard error
\[ \bar{x} = 50.2 \pm 2.3\text{ (SE)} \]
% Confidence intervals
\[ \text{95\% CI: } \mu = 100 \pm 1.96 \times \frac{\sigma}{\sqrt{n}} \]
% Range notation
\[ x \in [\mu - 2\sigma, \mu + 2\sigma] = \mu \pm 2\sigma \]Type $\pm$ in your LaTeX document. The command is \pm and it must be used in math mode (between dollar signs or in equation environments).
\pm produces the plus-minus symbol (±) while \mp produces the minus-plus symbol (∓). Use \mp when you need to indicate opposite signs, such as in $(a \pm b)(c \mp d)$.
No, \pm only works in math mode. To use it in text, wrap it in dollar signs: $\pm$. Alternatively, use the textcomp package with \textpm, but inline math is recommended for consistency.
Use: $5 \pm 2$. LaTeX automatically handles proper spacing around the symbol. For inline text: "The result is $5 \pm 2$ units."
The Unicode for ± is U+00B1. However, in LaTeX, always use \pm instead of copying the Unicode character directly, as LaTeX handles proper typesetting and spacing automatically.
Use \pm inside equation environments: \begin{equation} x = \frac{-b \pm \sqrt{b^2-4ac}}{2a} \end{equation}. The symbol works the same way in all math environments (equation, align, gather, etc.).
The \pm symbol automatically scales with the surrounding font size. In fractions or subscripts, it becomes smaller automatically. To change the overall size, change the font size of the entire math expression: {\large $5 \pm 2$}.
In tables, use math mode within cells: $25.3 \pm 0.2$. For complex tables with many values, consider using the siunitx package which provides special formatting for numbers with uncertainties.
\neq\lt, \gtNow that you know how to use the plus-minus symbol, create professional scientific papers, research documents, and technical resumes with our LaTeX templates.