17
Punctuation around formulae
In text math mode, commas and periods that are part of the
sentence should be outside math mode:
Because $f(a,b) = 0$, it follows that $f(2a, b-a) = 4$.
Because f(a;b) = 0, it follows that f(2a;b a) = 4.
In display math mode, there should (usually) be a comma,
semicolon, or period inside the display.
We find therefore that \[ x^{n} + y^{n} \ne z^{n}. \]
We nd therefore that
x
n
+y
n
6= z
n
:
33