deletions | additions       diff --git a/If_we_assume_vec_v__.tex b/If_we_assume_vec_v__.tex  index 5b83dce..4c437c5 100644  --- a/If_we_assume_vec_v__.tex  +++ b/If_we_assume_vec_v__.tex 
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If we assume  $$ \vec{v}(t) \Delta t = \vec{x}(t) \vec{x}(t+\Delta t)  - \vec{x}(t-\Delta t) $$ then