FixIt/apps/test/content/posts/mathjax-test.md

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title	date	collections	categories	tags	math
MathJax Test	2025-09-15T21:05:17+08:00	Tests	Markdown	Math	type mathjax mathjax macros loader packages tex bold {\bf #1} 1 load paths ui/safe [tex]/physics [custom]/xypic.js custom https://cdn.jsdelivr.net/gh/sonoisa/XyJax-v3@3.0.1/build/ [+] physics xypic physics italicdiff arrowdel false false

Testing \text{MathJax} rendering in FixIt theme.

Inline Formulas

c = \pm\sqrt{a^2 + b^2} and (f(x)=\int_{-\infty}^{\infty} \hat{f}(\xi) e^{2 \pi i \xi x} d \xi)

Formula Blocks

x = {-b \pm \sqrt{b^2-4ac} \over 2a}

[ f(a) = \frac{1}{2\pi i} \oint\frac{f(z)}{z-a}dz ]

\cos(\theta+\phi)=\cos(\theta)\cos(\phi)−\sin(\theta)\sin(\phi)

[ \int_D ({\nabla\cdot} F)dV=\int_{\partial D} F\cdot ndS ]

\vec{\nabla} \times \vec{F} =
            \left( \frac{\partial F_z}{\partial y} - \frac{\partial F_y}{\partial z} \right) \mathbf{i}
          + \left( \frac{\partial F_x}{\partial z} - \frac{\partial F_z}{\partial x} \right) \mathbf{j}
          + \left( \frac{\partial F_y}{\partial x} - \frac{\partial F_x}{\partial y} \right) \mathbf{k}

\sigma = \sqrt{ \frac{1}{N} \sum_{i=1}^N (x_i -\mu)^2}

(\nabla_X Y)^k = X^i (\nabla_i Y)^k =
           X^i \left( \frac{\partial Y^k}{\partial x^i} + \Gamma_{im}^k Y^m \right)

Chemical Equations

C_p[\ce{H2O(l)}] = \pu{75.3 J // mol K} \ce{Hg^2+ ->[I-] HgI2 ->[I-] [Hg^{II}I4]^2-} C_p[\ce{H2O(l)}] = \pu{75.3 J // mol K}

Custom Macros

\bold{Custom} macro \KaTeX in \text{MathJax}

\def\RR{{\bf R}}
\def\bolda#1{{\bf #1}}
\RR = \bolda{R}

\newcommand{\water}{{\rm H_{2}O}}
\water = \text{H}_2\text{O}

\newcommand{\hello}[1][World]{Hello, #1!}
\hello \quad \hello[FixIt]

\let\oldphi=\phi
\let\oldtheta=\theta
\renewcommand{\phi}{\varphi}
\renewcommand{\theta}{\vartheta}
\phi, \oldphi, \theta, \oldtheta

Custom Extensions

A physics package example:

\mqty(a & b \\ c & d) = \begin{pmatrix} a & b \\ c & d \end{pmatrix}

An xypic package example:

\begin{xy}
\xymatrix {
U \ar@/_/[ddr]_y \ar@{.>}[dr]|{\langle x,y \rangle} \ar@/^/[drr]^x \\
 & X \times_Z Y \ar[d]^q \ar[r]_p & X \ar[d]_f \\
 & Y \ar[r]^g & Z
}
\end{xy}