question_answer

The vector \[\frac{1}{3}\,(2\mathbf{i}-2\mathbf{j}+\mathbf{k})\] is                                   [IIT Screening 1994]

A)             A unit vector   

B)             Makes an angle \[\frac{\pi }{3}\] with the vector \[2i-4\mathbf{j}+3\mathbf{k}\]

C)             Parallel to the vector \[-\mathbf{i}+\mathbf{j}-\frac{1}{2}\mathbf{k}\]

D)           Perpendicular to the vector \[3\mathbf{i}+2\mathbf{j}-2\mathbf{k}\]