Vectors dividing a line in a ratio
Use the correct fraction along the segment.
- A vector has both magnitude and direction. Reverse a route by changing its sign.
- Use a consistent direction and match corresponding components.
- A scalar multiple proves parallel directions. Collinearity also needs a shared point.
Example 1
M divides AB in the ratio AM:MB = 1:2.
Find the position vector of M. The denominator uses the total number of parts.
Example 2
M divides AB in the ratio AM:MB = 2:2.
Find the position vector of M. The denominator uses the total number of parts.
Your turn
Question 1 Find the whole directed vector from A to B. Use 3 of the 5 total ratio parts. Add the route O → A → M.
M divides AB in the ratio AM:MB = 3:2.
Check answer
Question 2 Find the whole directed vector from A to B. Use 4 of the 6 total ratio parts. Add the route O → A → M.
M divides AB in the ratio AM:MB = 4:2.
Check answer
Question 3 Find the whole directed vector from A to B. Use 5 of the 7 total ratio parts. Add the route O → A → M.
M divides AB in the ratio AM:MB = 5:2.
Check answer
Question 4 Find the whole directed vector from A to B. Use 1 of the 4 total ratio parts. Add the route O → A → M.
M divides AB in the ratio AM:MB = 1:3.
Check answer
Question 5 Find the whole directed vector from A to B. Use 2 of the 5 total ratio parts. Add the route O → A → M.
M divides AB in the ratio AM:MB = 2:3.
Check answer
M divides AB in the ratio AM:MB = 3:2.
M divides AB in the ratio AM:MB = 4:2.
M divides AB in the ratio AM:MB = 5:2.
M divides AB in the ratio AM:MB = 1:3.
M divides AB in the ratio AM:MB = 2:3.