![captions - Undefined control sequence \begin{document} during compiling - TeX - LaTeX Stack Exchange captions - Undefined control sequence \begin{document} during compiling - TeX - LaTeX Stack Exchange](https://i.stack.imgur.com/zJrml.png)
captions - Undefined control sequence \begin{document} during compiling - TeX - LaTeX Stack Exchange
![cases - "Undefined control sequence" while using conditional equations in LATEX - TeX - LaTeX Stack Exchange cases - "Undefined control sequence" while using conditional equations in LATEX - TeX - LaTeX Stack Exchange](https://i.stack.imgur.com/7bICH.png)
cases - "Undefined control sequence" while using conditional equations in LATEX - TeX - LaTeX Stack Exchange
This erorr came again when I recompile 'thesis.tex' in another computer · Issue #204 · mohuangrui/ucasthesis · GitHub
![cases - "Undefined control sequence" while using conditional equations in LATEX - TeX - LaTeX Stack Exchange cases - "Undefined control sequence" while using conditional equations in LATEX - TeX - LaTeX Stack Exchange](https://i.stack.imgur.com/19khy.png)