det⁡[aj⁢k]=|a11a12a13a21a22a23a31a32a33|=a11⁢|a22a23a32a33|-a12⁢|a21a23a31a33|+a13⁢|a21a22a31a32|=a11⁢a22⁢a33-a11⁢a23⁢a32-a12⁢a21⁢a33+a12⁢a23⁢a31+a13⁢a21⁢a32-a13⁢a22⁢a31.