NTA Abhyas JEE Main2020MathematicsVector AlgebraPractice
If a → ,   b → and c → are three non-zero and non-coplanar vectors such that a → b → c → = 4 , then the value of a → + 3 b → - c → ⋅ a → - b → × a → - 2 b → - 3 c → is equal to
Options
- A40
- B44
- C48
- D52
Correct answer
D. 52
Step-by-step solution
a → + 3 b → - c → ⋅ a → - b → × a → - 2 b → - 3 c → = 1 3 - 1 1 - 1 0 1 - 2 - 3 a → b → c → = 1 3 - 3 - 3 - 1 - 2 + 1 × 4 = 13 × 4 = 5 2