the 3rd kine eqns, p1

  • First two equations, with v=v(t)v = v(t) and x=x(t)x = x(t), are v=v0+at,(I1)\tag{I1} v = v_0 + at, x=x0+v0t+12at2.(I2)\tag{I2} x = x_0 + v_0 t + \tfrac12 a t^2.
  • Turn (I1) into following t=vv0a.(I3)\tag{I3} t = \frac{v - v_0}{a}. and then substitute to (I2)