deletions | additions       diff --git a/layout.md b/layout.md  index 24dea8b..70a8798 100644  --- a/layout.md  +++ b/layout.md 
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Let_s_reformulate_1_and__.tex  Subsituting_4_into_1_vec__.tex  From_5_we_can_see__.tex  Inverse_is_also_true_if__.tex