Scottish National 5 Mathematics

National 5 Maths Vectors

Use directed line segments and two- or three-dimensional vector components, including magnitude.

Before you start

  • Keep components in a consistent order.
  • Decide whether a calculator supports the method; exact working may still be required.
  • Read the command word, record the units or requested form, and make the final answer match it.
National 5 Mathematics lesson

Explanation

Vectors is an assessed part of Scottish National 5 Mathematics in the geometry area. Use directed line segments and two− or three-dimensional vector components, including magnitude.

Keep components in a consistent order.

Add or subtract corresponding components.

Use Pythagoras across the components for magnitude.

The interactive bank below mixes direct skills, reverse questions, interpretation and contextual reasoning rather than repeating one number pattern.

Visual support

Vector as movement from A to B

ABAB = b - a

Key formulae and rules

  • AB = b − a
  • |(x, y)| = √(x² + y²)
  • |(x, y, z)| = √(x² + y² + z²)

Watch out

Changing the order of components.

Check

Check the direction and magnitude separately, keeping components in x, y, z order.

Exam tip

Mark the diagram with the values you use, show the formula and finish with the correct length, area or volume units.

Worked examples

Worked example 1

Vectors worked example

Find the magnitude of (2, −3, 6).

  1. Magnitude = √(2² + (-3)² + 6²)
  2. = √(4 + 9 + 36)

Answer: 7

Watch out

  • Changing the order of components.
  • Omitting the square root when finding magnitude.