# Gauss's (Divergence) theorem in Classical Electrodynamics

How does divergence theorem holds good for electric field. How does this hold true-

$$\iiint\limits_{\mathcal{V}} (\vec{\nabla}\cdot\vec{E})\ \mbox{d}V=\mathop{{\int\!\!\!\!\!\int}\mkern-21mu \bigcirc}\limits_{\mathcal{S}} {}\vec{E}\cdot\hat{n}\ \mbox{d}A$$