Uniform motion: dv/dt = 0 ds/dt = v (a constant) integral(dx) = v. integral(dt) => x = x(subsript 0) +vt ??? Uniform accelerated motion: dv/dt = constant Equations of motion are: dv/dt = a => v = v(subscript 0) + a.t ??? dx/dt = v => x = x(subscript 0) + v(subscript 0).t + 1/2.a.t^2 ??? v.dv/dt = a => v^2 = v(subscript 0)^2 + 2.a.(x-x(subcript 0)) ??? I don't understand the lines with question marks next to them.