c1-b1c2-(1/2)b2c3-(1/3)b3c3
x1-a1b1-a2b2/2-a3b3/3 a1 a2 a3
0 1 0 0
0 0 2 0
0 0 0 3
= 6(x1-a1b1-a2b2/2-a3b3/3)