##Math LaTeX formula with MathJax
###$ inline formula：
mass-energy conservation equation: $E=mc^2$
$x = x+1$
$\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}$
###$$ whole line formula：
\[x = x+1\] \[\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}\] \[\displaystyle \int \left(\frac{-1}{\sqrt{1 - \left(\frac{1}{x}\right)^{2}}}\right) \, \left(\frac{-1}{x^{2}}\right) dx\]###Reference