当λ=时, 2 10 22 B→01311)01311 0000000000 r(4)=r(B)=2<4,故方程组有无穷多解, 0 同解方程组为 X42 2 3x3-x4+1x2 3 2 2 2 xxx +k2 3 0 3 4 0 2 2 0 圆心, 21 当  = 时   → 0 0 0 0 0 0 1 3 1 1 1 0 21 21 1 B   − − → 0 0 0 0 0 0 1 3 1 121 21 1 0 1 r(A) = r(B) = 2  4,故方程组有无穷多解, 同解方程组为 === − − + = − − 4 4 3 3 2 3 4 1 3 4 3 121 21 x x x x x x x x x x . 021210 2021 0131 1 2 4321  − + −− + − =  k k xxxx