Plus-Minus. Means a quantity of same magnitude can have either a positive or a negative value. As commonly found in square roots such as
$$\sqrt[2]{625}= +-25$$.
Here is an Wikipedia SVG-example of a basic trigonometry formula:
How to render it using MathJax?
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ALSO;
Also I've seen use of minus-plus, i.e. .
I can't remember specific example but it was probably in some chemistry related text, in a situation; two variables (say $x$ and $y$) each have positive and negative value. But if $x$ is positive then $y$ is negative, and if $x$ is negative then $y$ is positive.
Don't know whether the second one is standard or not; but if the second-one is standard or allowed in MathJax; how to use it in MathJax formatting??
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PS. I've gone through MathJax basic tutorial and quick reference and also seen Google but could not find.
\pm
and\mp
$\endgroup$