deletions | additions       diff --git a/Inverse_is_also_true_if__.tex b/Inverse_is_also_true_if__.tex  index e370985..2d54f21 100644  --- a/Inverse_is_also_true_if__.tex  +++ b/Inverse_is_also_true_if__.tex 
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Inverse is also true, if we assume that  $$ \vec{v}(t) = \frac{\vec{x}(t+\Delta t) - \vec{x}(t-\Delta t)}{2 \Delta t} $$  $$(\vec a(t) + \vec a(t+\Delta t))\Delta t^2= \vec x(t-\Delta t) - \vec x(t) + \vec{x}(t+2 \Delta t) - \vec x(t+\Delta t) $$