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1.偏导

\frac{\partial f}{\partial x}

$$\frac{\partial f}{\partial x}$$

2.求导

\frac{\mathrm{d} y}{\mathrm{d} x}

$$\frac{\mathrm{d}y}{\mathrm{d}x}$$

3.形如$x^{{}^{\prime }}$求导

x^{'}

$$x^{{}^{\prime }}$$

4.形如$\dot{x}$求导

\dot x \ddot x

$$\dot{x}\ddot{x}$$

5.拉普拉斯算子$\nabla$

\nabla f

$$\nabla f$$