Keywords (AQA GCSE Further Maths): Revision Notes
GCSE Mathematics Keywords Guide
Understanding mathematical instruction words is crucial for exam success. These command words tell you exactly what type of response is expected, and knowing their precise meanings can make the difference between gaining full marks and losing valuable points.
Understanding command words
Mathematical exams use specific instruction words that have precise meanings. When you see these words in a question, they're giving you clear guidance about the type of answer required and the level of working you need to show. Let's explore what each of these key terms means and how to respond appropriately.
Critical for Exam Success
Command words are not suggestions - they are specific instructions that determine exactly what type of response the examiner expects. Misinterpreting a command word can cost you valuable marks even if your mathematical understanding is correct.
| Calculate | Work out the numerical value (often used after making a substitution) | |
|---|---|---|
| Draw (a graph) | Draw axes on graph paper, plot points accurately and join with a straight line or smooth curve | |
| Evaluate | Give a numerical value for your answer | |
| Expand | Remove brackets | |
| Expand and simplify | Remove brackets and collect like terms | |
| Explain | Give reasons, either in words, or using mathematical symbols, or both | |
| Expression | One or more terms, for example one side of a formula | |
| Factories | Write as a product | |
| Give your answer in its simplest form | Cancel answers given as ratios or fractions or collect like terms | |
| Hence | Use earlier work to deduce the result | |
| Hence or otherwise | Using previous work to deduce the result is an option | |
| Plot | Mark points (usually on graph paper) and join with a straight line or curve | |
| Prove | Show all relevant steps (include explanations of facts used in geometrical proofs) | |
| Show that | Show all relevant steps to reach a given result | |
| Sketch (a graph) | Do not use graph paper. Draw axes and show the correct shape in each quadrant. Label appropriate points (e.g. intersection with axes, stationary points) | |
| Verify | "Check out a statement or result that you have been given | |
| Work out the exact value of | Give the answer as an integer, fraction, recurring decimal, in terms of n, etc. or a surd | |
| Write down | The answer should be obvious (no working is necessary) |
Calculation and numerical work
Basic computational tasks
When you encounter Calculate, you need to determine a numerical result, often after making substitutions into formulas or expressions. This typically involves showing your working steps clearly and arriving at a specific number.
Evaluate requires you to find a numerical value for your final answer. This is similar to calculate but emphasises that you must give a specific numerical result rather than leaving your answer in algebraic form.
Worked Example: Calculate vs Evaluate
Calculate the area where length = 5cm and width = 3cm Step 1: Area = length × width Step 2: Area = 5 × 3 = 15cm²
Evaluate when Step 1: Substitute Step 2:
Work out the exact value of demands that you provide a precise answer, which might be in the form of a fraction, surd, or exact decimal rather than a rounded approximation. This instruction often appears when dealing with irrational numbers or when precision is particularly important.
Simple answers
Write down indicates that the answer should be immediately obvious from your previous work or from given information. No complex working is necessary - the solution should be straightforward to identify and state.
Understanding "Write down"
This command word appears when the answer should be clear from a graph, table, or previous calculation. If you find yourself doing complex working, you may have misunderstood the question.
Algebraic manipulation
Expanding and simplifying
Expand means you need to multiply out brackets to remove them from an expression. For example, expanding would give you .
Expand and simplify goes one step further - after removing brackets, you must collect like terms together to create the simplest possible form of the expression.
Worked Example: Expand and Simplify
Expand and simplify
Step 1: Expand the brackets
Step 2: Add the remaining term
Step 3: Simplify by collecting like terms
Give your answer in its simplest form requires you to ensure your final answer cannot be simplified further. This might involve cancelling fractions, collecting like terms, or expressing ratios in their lowest terms.
Working with expressions
An Expression refers to one or more mathematical terms - essentially one side of a formula or equation. When asked to write an expression, you're creating a mathematical phrase that represents a particular situation.
Factorise is the reverse of expanding - you need to write an expression as a product of its factors, typically by taking out common factors or recognising special patterns like difference of squares.
Expanding vs Factorising
These are opposite processes:
- Expanding:
- Factorising:
Drawing and graphing
Creating visual representations
Draw (a graph) requires you to use graph paper, plot points with precision, and connect them with either straight lines or smooth curves as appropriate. Accuracy is important, and you should include proper labelling of axes.
Plot specifically means marking points accurately, usually on graph paper, and joining them with straight lines or curves. The emphasis is on precise positioning of coordinates.
Sketch (a graph) has different requirements - you don't need graph paper, but you must show the correct overall shape in each quadrant. Key features like intercepts with axes and stationary points should be clearly labelled and positioned correctly.
Draw vs Sketch - Key Differences
- Draw: Requires graph paper, precise plotting, accurate measurements
- Sketch: Focuses on correct shape and key features, doesn't need graph paper
- Both require proper labelling of axes and key points
Reasoning and proof
Logical demonstration
Prove demands that you demonstrate all relevant steps, including explanations of mathematical facts used, particularly in geometrical proofs. Every statement must be justified logically.
Show that requires you to demonstrate all relevant steps to reach a specific given result. You're working towards a predetermined conclusion and must show the complete logical path.
Verify means you need to check or confirm a statement or result that has been provided to you. This involves substituting values or working backwards to confirm the given information is correct.
Worked Example: Show that
Show that
Step 1: Expand the left side
Step 2: Subtract ✓
Using previous work
Hence tells you to use your earlier work to determine the next result. This creates a logical connection between different parts of a question.
Hence or otherwise gives you the option to use previous work to find the result, but you can choose an alternative method if you prefer.
Making the Most of "Hence"
When you see "hence," look back at your previous answer. The question is designed so that your earlier work makes the next part easier. Don't start from scratch!
Communication and explanation
Explain requires you to provide reasons for your answer, either in words, through mathematical symbols, or both. You need to make your reasoning clear and justify your conclusions.
Key Points to Remember:
- Command words have precise meanings - read them carefully and respond exactly as required
- "Calculate" and "evaluate" need numerical answers with working shown
- "Expand" removes brackets, while "factorise" creates them
- "Draw" needs accuracy on graph paper, "sketch" shows correct shape and key features
- "Prove" and "show that" require complete logical justification of every step
- "Hence" means use your previous work - don't start from scratch!