How do i use mathmatical symbols

This should help

 

You can learn how to make the LaTeX symbols (clicking on an image will show you the text you need to use)


Also, many text symbols can be made:

& radic ; = √
& rarr ; = →
& alpha ; = α
& Psi ; = Ψ
& infin ; = ∞


Not to mention anything you can look up in the Character Map in windows (provided you're looking at the right font)

For example, a degree symbol (°) can be made by typing ALT-0176. (You must use the numeric pad, and hold alt throughout the entire sequence)

 

[tex] S = \sum_{n=0}^\infty \frac{i^n}{n!} \idotsint \ {d^4x_1}\ {d^4x_2}
\dots \ d^4x_n \ T (H_I(x_1) \ H_I(x_2) \dots \ H_I(x_n) )
[/tex]

 

You can copy and paste from here.