0-11/2 001-21/2 00000 由于R(4)=R(B)=2,故方程组有解,且有 ,=n+x 2 4 +1/2 x1=x2+x4+1/2 x,=x,+0x x2=2x4+12 3=0x2+2x4+1/2 x4=0x2+x4. 0 0 0 0 0 0 0 1 2 1 2 1 1 0 1 1 2 ~           − − − 由于R(A) = R(B) = 2, 故方程组有解，且有    = + = + + 2 1 2 1 2 3 4 1 2 4 x x x x x        = + = + + = + = + +  4 2 4 3 2 4 2 2 4 1 2 4 0 0 2 1 2 0 1 2 x x x x x x x x x x x x