Text box or rich text box only receive characters or unicodes. Math expressions can be put in the form of something like "((x-x0)/a)^2 + ((y-y0)/b)^2 = r^2".If you mean putting math symbols like human written style, I think you have to render them with Win32 GDI/GDI+/...
To use jqMath on your site,download jqMath, and open the included COPY-ME.html file as UTF-8 in a text editor. Mathematical Symbols for the Web By default, jqMath knows the MathML precedence of everyMathML 3 operator symbol, except we omit “multiple character operators” like&∨<=, ...
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