The elements of these 2 by 2 matrices come from the original matrix. Each possible set of 4 (2 by 2) elements is taken to make a rectangle and then include the 1,1 element (the so-called pivot)
The elements of these 2 by 2 matrices come fromthe original matrix. Each possible set of 4 (2 by 2) elements is taken to make a rectangle and then includethe 1,1 element (the so-called pivot)