Test math

<math>E=mc^2</math>

<math>2 + 2 = 4</math>

<math>x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}</math>

<math>a^2 + b^2 = c^2</math>

<math>e^{i\pi} + 1 = 0</math>

<math>\int_0^\infty e^{-x^2} dx = \frac{\sqrt{\pi}}{2}</math>

<math>\sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{6}</math>

<math>\begin{pmatrix} 1 & 2 \\ 3 & 4 \end{pmatrix}</math>

<math>\frac{d}{dx} \left( x^2 \right) = 2x</math>

<math>(x + y)^n = \sum_{k=0}^n \binom{n}{k} x^{n-k} y^k</math>

<math>\lim_{x \to 0} \frac{\sin x}{x} = 1</math>

<graphviz> digraph G {

   A -> B;
   B -> C;
   C -> D;
   D -> A;

} </graphviz>

Each test has a different page, so it can avoid single test page too long.