User:Mr Li

渲染测试

$\frac{d}{dt}\left(\frac{\partial L}{\partial {\dot{q}}_i}\right)-\frac{\partial L}{\partial q_i}=0$

$$\frac{f(b)-f(a)}{g(b)-g(a)}=\frac{f^{\prime }(\xi )}{g^{\prime }(\xi )}$$

$\mathrm{H}{\phantom{A}}_2\mathrm{O}\stackrel{-\rightharpoonup }{\leftharpoondown -}\mathrm{H}{\phantom{A}}^{+}+\mathrm{O}\mathrm{H}{\phantom{A}}^{-}$

$\mathrm{C}\mathrm{O}{\phantom{A}}_2+\mathrm{C}⟶2\mathrm{C}\mathrm{O}$

这是一段话