2.5. Right three vectors

Let a, b, c be three non-coplanar vectors. It is said that the vectors a, b, c form the right three of vectors , if their mutual arrangement in space can be compared with three fingers of the right hand: a - with big, b - with index finger, c - with middle one. If the vectors a, b, c are matched with the same fingers of the left hand, then they are said to form the left three of vectors .