You use your vast 😉 knowledge of permissable LaTeX syntax in the Pages equation editor (Insert menu : equation…) like the following, to embed the equation in your Pages document:

Pages incorporates its built-in, blahtex LaTeX/MathML translator to do the equation syntax conversion.
Click the blahtex link to download its PDF manual from the Apple article, About LaTeX and MathML support in Pages, Numbers, Keynote, and iBooks Author, and that manual will contain supported syntax operators, and tables for these math and other symbols that you can use.
Ensure that in Pages Preferences : General, that Insert equations with MathType is unchecked, so that you can use the Pages internal equation editor.