deletions | additions       diff --git a/begin_equation_frac_d_dA__.tex b/begin_equation_frac_d_dA__.tex  index 7efbfab..be51ca3 100644  --- a/begin_equation_frac_d_dA__.tex  +++ b/begin_equation_frac_d_dA__.tex 
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\begin{equation*}  \frac{d}{dA}\int_G \frac{d}{d\mathcal{A}}\int_G  \rho dV = - \int_{\partial G}f \cdot n \,dS\nonumber \end{equation*}