Update textbook.en.md

10.brainstorming-innovative-courses/intercambio-curso-electromagnetismo/textbook.en.md

@@ -696,11 +696,11 @@ $`\displaystyle\oiint_S\vec{B}\cdot\vec{dS}=0`$
 $`\displaystyle\iiint_{\tau} div\vec{E} \cdot d\tau= \displaystyle\iiint_{\tau} \dfrac{\rho}{\epsilon_0} \cdot d\tau = \dfrac{1}{\epsilon_0} \cdot \iiint_{\tau} \rho \cdot d\tau = \dfrac{Q_{int}}{\epsilon_0} `$
 
 
-$`\displaystyle\iint_S \overrightarrow{rot}\,\overrightarrow{E}\cdot dS = -\displaystyle\iint_S \leftrightarrow \tau} \overrightarrow{B}}\cdot dS`$
+$`\displaystyle\iint_S \overrightarrow{rot}\,\overrightarrow{E}\cdot \overrightarrow{dS} = -\displaystyle\iint_S \leftrightarrow \tau} \overrightarrow{B}\cdot \overrightarrow{dS}`$
 
 Mecánica newtoniana : espacio y el tiempo son desacoplados $`\Longrightarrow`$ orden de integración / derivación entre variables de espacio y tiempo no importa.
 
-$`\displaystyle\iint_S \overrightarrow{rot}\,\overrightarrow{E}\cdot dS = - \dfrac{\partial}{\partial t} \left( \displaystyle\iint_S \overrightarrow{B}\cdot dS\right)`$
+$`\displaystyle\iint_S \overrightarrow{rot}\,\overrightarrow{E}\cdot \overrightarrow{dS} = - \dfrac{\partial}{\partial t} \left( \displaystyle\iint_S \overrightarrow{B}\cdot \overrightarrow{dS}\right)`$
 
 Ostrogradsky’s theorem : for all vectorial field $`\vec{X}`$,