deletions | additions       diff --git a/Now_vec_v_t_Delta__.tex b/Now_vec_v_t_Delta__.tex  index ac86a55..4d5f867 100644  --- a/Now_vec_v_t_Delta__.tex  +++ b/Now_vec_v_t_Delta__.tex 
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$$\vec x(t+\Delta t)=\vec x(t) + \vec x(t)-\vec x(t-\Delta t)+\frac{1}{2}\vec a(t)\,\Delta t^2+\frac{1}{2}\vec a(t)\,\Delta t^2$$  $$\vec x(t+\Delta t)=\vec x(t) + \vec{v}(t) \Delta t +\frac{1}{2}\vec a(t)\,\Delta t^2$$ Which is \textit{exactly} (1) $\not\Delta$