A simple equation for a line in $\mathbb{R}^2$:

\[ y = mx + b \]

Again, but with dollar signs:

$$ y = mx + b $$

# Regarding $\vec g$ and its effects

Math in a heading

~~~~ {.haskell}
f x = length $ tail x
~~~~

$x + 1$

$e_{ik}$ in the statement the theorem about $V_k$

$**η = (-1)^{k(n-k)}sη$, where $**η$, is the Hodge star applied twice.

\[ a_1 \]
This is neither math nor italic
\[ a_2 \]

Support brackets with two backslashes, as do MultiMarkdown and Pandoc:

\\[
\Gamma(x) = \int_0^\infty t^{x-1}{\mathrm{e}}^{-t}\,{\mathrm{d}}
\\]

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