Sequences, straight-line graphs and function notation
Pearson Edexcel International GCSE Mathematics · 4MA1
Paper 1F | Whole paper: Number, Algebra, Geometry, Statistics
Finding the rule of a sequence, drawing and interpreting linear graphs, and — at Higher — using function notation and inverse functions.
Specification coverage
3 Sequences, functions and graphs — statements 3.1–3.4 (Foundation and Higher Tier)
Assessment objectives: AO1. Suggested learning time: 90 minutes.
Required knowledge
- Generate terms of a sequence using term-to-term and position-to-term rules
- Find the nth term of a linear sequence
- Recognise and use the equation y = mx + c, including gradient and intercept
- Find the equation of a straight line through given points
- Higher: quadratic sequences, function notation, composite and inverse functions
Required skills
- Derive an nth term from a sequence without guessing
- Read a gradient from a graph and interpret it in context
- Find the equation of a line parallel or perpendicular to a given line (Higher)
How it is examined
- Structured questions building from a routine start to a multi-step finish
- Problem-solving questions with no method given
- 'Show that' and reasoning questions where the working IS the answer
Common mistakes
- Giving 'add 4' as the nth term. That is the term-to-term rule; the question asks for a rule in terms of n.
- Reading the gradient as the change in x over the change in y. It is the other way round.
- Forgetting that perpendicular gradients multiply to −1, so the perpendicular of 2 is −½.