Consider r , a , b and c are non-zero vectors such that r a =0 , | r b |=| r || b |,| r c |=| r || c | , then [ a b c ] is

Step-by-step solution

Here, it is given in problem | r b |=| r || b | So, it is clear that angle between r and b is 2 r a =0 r is perpendicular to a . | r c |=| r | | c | r is perpendicular to c . Thus, r is perpendicular to a , b and c . Hence, a , b and c are coplanar. [ a b c ]=0