Test math.

$\frac{a^b}{\sqrt{x^2+u_n}}$

$\frac{a^b}{\sqrt{x^2+u_n}}$

$1 = \frac{1}{\sqrt{2\pi} \sigma} \left( \int_{-\infty}^\infty e^{-\frac{1}{2\sigma^2} (x-\mu)^2} \, dx \right)$.

$\frac{1}{1-x} = 1 + x + x^2 + x^3 + \dotsb = \sum_{n=0}^\infty x^n$.

$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$.

$df = \frac{\partial f}{\partial x^1} \, dx^1 + \frac{\partial f}{\partial x^2} \, dx^2 + \dotsb + \frac{\partial f}{\partial x^n} \, dx^n$.

$\sin \pi z = \pi z \prod_{n=1}^\infty \left( 1 - \frac{z^2}{n^2} \right)$.

$\lVert y \rVert = \left( y_1^2 + y_2^2 + \dotsb + y_k^2 \right)^{1/2}$.