自用的markdown与latex特殊符号

\triangleq
\approx
\xlongequal[y=\arctan x]{x=\tan y}
\sum_{\substack{j=1 \\ j\neq i}}
\iiint\limits_\Omega
\overset{\circ}{\vec{r}}
\varphi
\checkmark
\stackrel{\cdot\cdot\cdot}{x}

≜ ≈ = y = arctan ⁡ x x = tan ⁡ y ∑ j = 1 j ≠ i ∭ Ω r ⃗ ∘ φ ✓ x ⋅ ⋅ ⋅ \triangleq \approx \xlongequal[y=\arctan x]{x=\tan y} \sum_{\substack{j=1 \\ j\neq i}} \iiint\limits_\Omega \overset{\circ}{\vec{r}} \varphi \checkmark \stackrel{\cdot\cdot\cdot}{x} ≜≈x=tany y=arctanxj=1j=i∑Ω∭r ∘φ✓x⋅⋅⋅
LaTeX \LaTeX LATEX Mathematical Symbols
List of LaTeX mathematical symbols -oeis
List of Greek letters and math symbols -overleaf