Hi. Writing math is already implemented in Obsidian through MathJax.
- Advanced formatting syntax - Obsidian Help
- MathJax basic tutorial and quick reference - Mathematics Meta Stack Exchange
In LaTeX you can use packages to have custom syntax for various things like automatic equation numbering, SI units, localised number forms, localised dates etc. In MathJax you don’t have access to every package. Instead MathJax uses preconfigured packages. Most notably you don’t get automatic equation numbering. There is a community plugin LaTeX-like Theorem & Equation Referencer that brings automatic equation numbering to your notes.
Live preview may cause problems when using MathJax so usually you need to use source mode for editing. You can use Split right command to have two views simultaneously—one for source view and one for rendered view (reading view). Use command palette to run commands.
Finally see also this plugin