(a)基础解系﹙0,0,1,0﹚′,﹙1,-1,0,1﹚′
﹙b)基础解系﹙0,1,1,0﹚′﹙1,1,0,-1﹚′
求公共解
a﹙0,0,1,0﹚′+b﹙1,-1,0,1﹚′=c﹙0,1,1,0﹚′+d﹙1,1,0,-1﹚′得到a=b=c=d=0
公共解只有零解.
,(a):x1+x2=0;x2-x4=0秩为2,自由变量x3,x4.﹙x3,x4﹚=﹙1,0﹚得到(x1,x2,x3,x4﹚'=﹙0,0,1,0﹚′﹙x3,x4﹚=﹙1,1﹚,得到(x1,x2,x3,x4﹚'=﹙1,-1,0,1﹚′