FatalMath Mode
Bad Math Environment Delimiter
! LaTeX Error: Bad math environment delimiter.
What this error means
A display math delimiter (\[ or \]) was used in an invalid context — such as closing a display math block that was never opened, or opening display math inside inline math.
Common causes
- A \] without a preceding \[ to open display math
- A \[ inside an equation or align environment
- Unbalanced or nested math delimiters
How to fix it
Ensure every \[ is paired with exactly one \]. Do not nest display math inside other math environments. Use \( and \) for inline math, \[ and \] for unnumbered display math, or \begin{equation} for numbered equations.
Code examples
Causes the error
\documentclass{article}
\begin{document}
\] x = 5 \[ % Delimiters in wrong order
\end{document}Fixed
\documentclass{article}
\begin{document}
\[ x = 5 \] % Correct order
\end{document}Related errors
Test the fix live
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