MathJax.js

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        jax: ["input/TeX","output/HTML-CSS"],
        tex2jax: { inlineMath: [ ['$','$'], ["\\(","\\)"] ],
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        "HTML-CSS": { availableFonts: ["TeX"],
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$$\int_{-\infty}^{\infty} \frac{\sin(x)}{x} dx = \frac{\pi}{2}$$