%
% Example 2 from Section 2.5
%
A = [2 4 -1 5 -2; -4 -5 3 -8 1; 2 -5 -4 1 8; -6 0 7 -3 1]
C = [A eye(4)]
C(2,:) = C(2,:) + 2 * C(1,:)
C(3,:) = C(3,:) - C(1,:)
C(4,:) = C(4,:) + 3 * C(1,:)
C(3,:) = C(3,:) + 3 * C(2,:)
C(4,:) = C(4,:) - 4 * C(2,:)
C(4,:) = C(4,:) - 2 * C(3,:)
U = C(:,1:5)
E = C(:,6:9)
L = inv(E)
U
L * U
A
