六、设有含参数λ的线性方程组-|||- ) (x)_(1)+lambda (x)_(2)-(x)_(3)=0 (x)_(1)-(x)_(2)+lambda (x)_(3)=2 2(x)_(1)-(x)_(2)+(x)_(3)=3 .-|||-问λ取何值时,此方程组有唯一解,无解,无穷多解?在有无穷多解时求通-|||-解(10分).