data/mathematical/75.mml
<math xmlns='http://www.w3.org/1998/Math/MathML' display='inline'><semantics><mrow><mi>D</mi><mrow><mo>(</mo><mi>ρ</mi><msub><mi>u</mi> <mi>i</mi></msub><mo>)</mo></mrow><mo stretchy="false">/</mo><mi>D</mi><mi>t</mi><mo>≈</mo><mn>0</mn></mrow><annotation encoding='application/x-tex'>D\left(\rho u_i\right)/Dt\approx0</annotation></semantics></math>