deletions | additions       diff --git a/4-Dimensions.tex b/4-Dimensions.tex  index 82b1699..4752dae 100644  --- a/4-Dimensions.tex  +++ b/4-Dimensions.tex 
...
t_2 & x_2 & y_2 & z_2 \\  t_3 & x_3 & y_3 & z_3 \\  \end{vmatrix}  =\textbf{i}\begin{vmatrix}  x_1 & y_1 & z_1 \\  x_2 & y_2 & z_2 \\  x_3 & y_3 & z_3 \\  \end{vmatrix}  +...  \end{equation}