Answer: (na + mb)/(m+n).
- A (ma + nb)/(m+n)
- B (na + mb)/(m+n)
- C (ma - nb)/(m-n)
- D (a + b)/2
Correct answer: B. (na + mb)/(m+n)
Explanation: Internal division: position vector = (mb + na)/(m+n). For midpoint (m=n=1): (a+b)/2.
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