Answer: 120.
- A 60
- B 30
- C 120
- D 5
Correct answer: C. 120
Explanation: Scalar triple product is multilinear: [2a, 3b, 4c] = 2·3·4·[a, b, c] = 24×5 = 120. Each scalar factor on a vector multiplies out of the determinant independently. Answer: 120.
Triangle law of vector addition: placing vector b at the head of vector a, the diagonal from the start to the final head gives the resultant a + b.
Concept context
Vectors, dot product, cross product, and geometric applications