deletions | additions       diff --git a/documentclass_a4paper_11pt_article_begin__.tex b/documentclass_a4paper_11pt_article_begin__.tex  index 9547e50..90cd3c4 100644  --- a/documentclass_a4paper_11pt_article_begin__.tex  +++ b/documentclass_a4paper_11pt_article_begin__.tex 
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\documentclass[a4paper, 11pt]{article}  \begin{document}  \[x_{t-1}=\left(\begin{array}{c}  x_1\\  x_2\\  \vdots\\