deletions | additions       diff --git a/4-Dimensions.tex b/4-Dimensions.tex  index 6f2459b..adf9393 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 \\  & 0 & & \\  & & 0 & \\  & & & 0  \end{bmatrix}  \end{equation}