Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "http://localhost:6011/en.wikipedia.org/v1/":): {\displaystyle \begin{eqnarray} E &=& mc^2 \\ m &=& \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}} \end{eqnarray}}