changes.mady.by.user Arthur Aslanyan (Nafta College)
Saved on May 23, 2021
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\frac{\partial s}{\partial t} + q \frac{\partial }{\partial x} \left( \frac{q \, f}{\phi \, A } \right) = 0
s(t=0,x) = 0
s(t,0) = 1