VEC009 · Vectors · Classes 11–12
Position vector
The position vector of a point is the vector from the origin to it. The vector from A to B is b − a.
AB = b − aPosition vector
📐 Formula
AB→ = b − a
✏️ Worked example
A(1, 2), B(4, 6): AB = (3, 4), length 5.
🌍 Where it is used
Robot moves, game positions, navigation.
❓ Quick check
A(2, 1), B(5, 5). AB = ?
🏋️ Practice
EasyPosition vector of (−3, 2)?
Answer: −3i + 2j
MediumA(0, 0), B(5, −2). AB?
Answer: (5, −2)
ChallengeBA in terms of AB?
Answer: −AB