We solved the differential equation (2.29), mi,y = —b(vy — vmr), for the velocity of an object falling through air, by inspection — a most respectable way of solving differential equations. Nevertheless, one would sometimes like a more systematic method, and here is one. Rewrite the equation in the "separated" form m dv Y —b dt V y Vter and integrate both sides from time 0 to t to find vy as a function of t. Compare with (2.30).