Vectors

Vectors describe movement using direction and magnitude. They are used in geometry and link closely to coordinates and transformations.

Overview

A vector tells you both size and direction.

In GCSE Maths, vectors are often used to describe movement from one point to another.

\( \begin{pmatrix} 3 \\ 2 \end{pmatrix} \)

This vector means move 3 units to the right and 2 units up.

Unlike normal lengths, vectors include direction as well as distance.

What you should understand after this topic

  • Understand what a vector represents
  • Write vectors in column form
  • Describe movement using vectors
  • Add and subtract vectors
  • Understand how vectors appear in geometry and proof questions

Key Definitions

Vector

A quantity with both size and direction.

Scalar

A quantity with size only, such as length or mass.

Magnitude

The size or length of a vector.

Direction

The way the vector points.

Column Vector

A vector written vertically in brackets.

Directed Line Segment

A line showing both distance and direction from one point to another.

Key Rules

Top number = horizontal

Positive means right, negative means left.

Bottom number = vertical

Positive means up, negative means down.

Add matching parts

Add the top numbers together and the bottom numbers together.

Subtract matching parts

Subtract top from top and bottom from bottom.

Quick Movement Guide

\(\begin{pmatrix} 4 \\ 0 \end{pmatrix}\)

4 right

\(\begin{pmatrix} -2 \\ 0 \end{pmatrix}\)

2 left

\(\begin{pmatrix} 0 \\ 5 \end{pmatrix}\)

5 up

\(\begin{pmatrix} 0 \\ -3 \end{pmatrix}\)

3 down

How to Solve

Step 1: Read a vector as movement

A column vector shows horizontal and vertical movement.

\(\begin{pmatrix} 5 \\ 2 \end{pmatrix}\)
Top = horizontal movement.
Bottom = vertical movement.
This means 5 right and 2 up.
Vector movement on grid showing horizontal and vertical components

Step 2: Negative components

\(\begin{pmatrix} -3 \\ -4 \end{pmatrix}\)
Negative top → left.
Negative bottom → down.

Step 3: Add and subtract

\(\begin{pmatrix} 3 \\ 1 \end{pmatrix} + \begin{pmatrix} 2 \\ 4 \end{pmatrix} = \begin{pmatrix} 5 \\ 5 \end{pmatrix}\)
Add top with top, bottom with bottom.

Step 4: Multiply by a scalar

\(3\begin{pmatrix} 2 \\ -1 \end{pmatrix} = \begin{pmatrix} 6 \\ -3 \end{pmatrix}\)

Step 5: Vector between two points

Use B − A.

\(A(2,1),\ B(7,4)\)
Horizontal: \(7 - 2 = 5\)
Vertical: \(4 - 1 = 3\)
\(\begin{pmatrix}5 \\ 3\end{pmatrix}\)

Step 6: Exam method

See transformations for translation vectors.
  1. Read horizontal (top).
  2. Read vertical (bottom).
  3. Use negatives for left/down.
  4. Add/subtract components.
  5. Use B − A for direction.

Example Questions

Edexcel

Exam-style questions focusing on reading column vectors as movements.

Edexcel

The vector \( \begin{pmatrix} 2 \\ 5 \end{pmatrix} \) is shown on the grid.

2 right 5 up

Describe the movement.

Edexcel

The vector \( \begin{pmatrix} -4 \\ 1 \end{pmatrix} \) is shown on the grid.

4 left 1 up

Describe the movement.

AQA

Exam-style questions focusing on adding and subtracting column vectors.

AQA

Work out \( \begin{pmatrix} 3 \\ 2 \end{pmatrix} + \begin{pmatrix} 1 \\ 4 \end{pmatrix} \).

(3, 2) (1, 4) resultant
AQA

Work out \( \begin{pmatrix} 6 \\ 1 \end{pmatrix} - \begin{pmatrix} 2 \\ 3 \end{pmatrix} \).

subtract components 6 - 2 = 4 1 - 3 = -2

OCR

Exam-style questions focusing on vectors between points and describing translations.

OCR

Point A has coordinates (1, 2) and point B has coordinates (5, 7).

A(1,2) B(5,7) +4 +5

Find the vector from A to B.

OCR

Point P is moved by vector \( \begin{pmatrix} -3 \\ 4 \end{pmatrix} \).

P P' 3 left 4 up

Describe the movement.

OCR

A shape is translated by \( \begin{pmatrix} 4 \\ -2 \end{pmatrix} \).

original image 4 right, 2 down

Describe the translation.

Exam Checklist

Step 1

Check which part is horizontal and which is vertical.

Step 2

Watch the signs carefully.

Step 3

Add or subtract the matching numbers only.

Step 4

If working between points, subtract coordinates in the correct order.

Most common exam mistakes

Wrong direction

Positive and negative movements mixed up.

Wrong order

Top and bottom parts confused.

Wrong subtraction

Subtracting the coordinates in reverse.

Coordinate confusion

Treating a vector like a plotted point rather than a movement.

Common Mistakes

These are common mistakes students make when working with vectors in GCSE Maths.

Mixing up horizontal and vertical movement

Incorrect

A student swaps the x and y components of a vector.

Correct

Vectors are written as \(\begin{pmatrix} x \\ y \end{pmatrix}\), where x is horizontal movement and y is vertical movement.

Misunderstanding negative values

Incorrect

A student ignores the direction of negative components.

Correct

Negative values show direction: negative x is left, negative y is down.

Subtracting in the wrong order

Incorrect

A student reverses the subtraction when finding a vector.

Correct

To find the vector from A to B, calculate \(B - A\), not \(A - B\).

Treating vectors like coordinates

Incorrect

A student reads a vector as a point on a grid.

Correct

A vector represents movement, not position. It shows how far and in what direction to move.

Arithmetic errors in calculations

Incorrect

A student makes mistakes when adding or subtracting vectors.

Correct

Add and subtract vectors component-wise and check calculations carefully.

Try It Yourself

Practise solving problems involving vectors.

Questions coming soon
Foundation

Foundation Practice

Understand vector notation, directions and simple vector addition/subtraction.

Question 1

Which of the following is a vector?

Games

Practise this topic with interactive games.

Games coming soon.

Frequently Asked Questions

What is a vector?

A quantity with direction and magnitude.

How are vectors written?

As column vectors or with arrows.

What does vector addition mean?

Combining movements.