section_heading: Jednadžba tlaka
paragraph_text: <math> \frac{\partial }{\partial x_i} \left( \frac{\partial p}{\partial x_i} \right) =  - \frac{\partial }{\partial x_i} \left[ \frac{\partial \left( \rho u_i u_j \right)}{\partial x_j} \right] </math>