Hệ nào sau đây phụ thuộc tuyến tính:

\[\left\{ {{{\rm{u}}_1} = ( - 2,1, - 1),{{\rm{u}}_2} = (1, - 1, - 1),{{\rm{u}}_3} = ( - 1,0, - 2)} \right\}\]

\[\left\{ {{{\rm{u}}_1} = (1,1,2),{{\rm{u}}_2} = (1, - 1, - 1),{{\rm{u}}_3} = (2,1,1)} \right\}\]

\[\left\{ {{{\rm{u}}_1} = (1,1);{{\rm{u}}_2} = ( - 1,1),{{\rm{u}}_3} = (2,1,1)} \right\}\]

\[\left\{ {{{\rm{u}}_1} = (1,1,0);{{\rm{u}}_2} = (0,1,0),{{\rm{u}}_3} = (0,0,1)} \right\}\]