For the more common text symbols use the following commands. The ctexart document class here is provided by the ctex bundle which implements common Chinese typesetting practices. A collection of free latex templates.
LaTeX Mathematics Wikibooks The wikibook chapter on math in latex.
Enter your question or answer choice and when you want to insert an equation type your equation followed by the rest of your question. And a visible space can be created with textvisiblespace. From Wikibooks open books for an open world LaTeX. As it is virtually impossible to list all the symbols ever used in mathematics only those symbols which occur often in mathematics or mathematics education are included.