deletions | additions       diff --git a/4-Dimensions.tex b/4-Dimensions.tex  index adf9393..8d4fba6 100644  --- a/4-Dimensions.tex  +++ b/4-Dimensions.tex 
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\textbf{r}_1 \otimes \textbf{r}_2 =  \begin{bmatrix}  0 & y_1z_2-z_1y_2 & z_1x_2-x_1z_2 & x_1y_2-y_1x_2 \\  & z_1y_2-y_1z_2&  0 & t_1z_2-z_1t_2  & y_1t_2 - t_1y_2  \\ & & 0 & \\  & & & 0