求下列非齐次线性方程组的通解 X1+2X2-2X3+X4=-1 -X1-3X2+2X3+3X4=4 注；数字在右边的为X的右下角 求步骤

增广矩阵 (A,b)= 1 2 -2 1 -1 -1 -3 2 3 4 r2+r1 1 2 -2 1 -1 0 -1 0 4 3 r1+2r2, r2*(-1) 1 0 -2 9 5 0 1 0 -4 -3 所以方程组的通解为 (5,-3,0,0)^T+c1(2,0,1,0)^T+c2(-9,4,0,1)^T