Let be a vector coplanar with the vectors and . If is perpendicular to and , then is equal to :
- (A)84
- (B)336✓ Correct
- (C)315
- (D)256
Answer: (B)
Solution
Being coplanar with and , write . Perpendicularity to gives , so . The condition gives , that is ; with this yields , so and . Then and .
JEE Main · 2018 · 08 Apr 2018 · Offline · Single correct option