还是发个常用代码对照表吧 \frac{a}{b} {x}^{ab} {x}_{12} \sqrt{xyz} \sqrt[{x}]{{y}} 或 \sqrt%5B{x}%5D{{y}} \log_{a}{x} C_{m}^{n} \sqrt{a^2}=|a| \sum_{k=1}^{n}{a_k} \prod_{k=1}^{n}{a_k} \lim_{k\to \infty}{k^{-1}}=0 \int_{a}^{b}{f(x)dx} \pm1,\mp1 \Rightarrow,\Leftarrow,\Leftrightarrow \ne,\le,\ge,\equiv f'(x)\in [a,b] 或 f'(x)\in%5B a,b%5D \tan{30^{\circ}}=\frac{1}{\cot{30^{\circ}}} \pi,\alpha,\beta,\gamma,\theta,\lambda {a}\cdot{b},{a}\times{b},{a}\div{b} \Delta,\bigtriangleup,\odot,\angle,\perp \forall,\exists,\emptyset {{n}\choose{m}} f(x)={\left\lbrace{{1},{x>0}\\{0},{x<0}} 本文来源：https://www.wddqw.com/doc/e18a6709763231126edb1140.html