What the examiners said about Edexcel A Level Maths — and exactly what to do about it
We read every Pearson Edexcel examiner report for 9MA0 from June 2024 to June 2025, mapped each question to a topic, and turned the comments into a checklist of the mistakes that cost the most marks.
Summaries are in our own words with links to the originals. Predictions are informed guesses, not a guarantee.
Ranked for June 2027
What to focus on for June 2027
June 2026 papers have been sat, but their examiner reports were not publicly readable when we compiled this page. We will add them when they are. Ranked by how often each area appeared, how many marks it carried and how weakly it was answered.
Informed prediction, not a guarantee: any topic on the specification can be examined.
1
Functions: inverse, composite, modulus and domain/range
The largest block of marks on both Pure papers in both years we read (about 43 marks in 2024 and 51 in 2025), and the domain of an inverse is called out in both reports as still being missed.
High confidence9MA0/01 2024 Q6, Q8; 2025 Q19MA0/02 2025 Q12
Examined in every Pure paper we read (5–6 questions a year, roughly 30 marks), with by-parts sign errors and separating variables flagged in both series.
High confidence9MA0/02 2024 Q11, Q129MA0/01 2025 Q13, Q169MA0/02 2025 Q10
Differentiation, including implicit and parametric
Around 44 marks in 2024 and 28 in 2025; implicit/parametric questions appeared both years and "show that" differentiation lost the final mark for missing f′(x) =.
High confidence9MA0/01 2024 Q4, Q59MA0/02 2024 Q10, Q159MA0/02 2025 Q15
The 10 mistakes that cost the most marks (and 5 more)
Ordered by how often and how widely they were reported. The first 5 are free in full; Pro unlocks the fix and a worked example for every other one.
#1"Show that": skipped steps, working back from the answer, no final line
What examiners saw: The most repeated comment across papers. When the answer is printed, the marks are for the route. Candidates jump steps, work backwards from the given result, or finish without writing the given line (e.g. the "= 0" or "f′(x) =").
Fix: Start from the question, write every line, and end with exactly the printed result. If the answer is an equation, include "= 0".
Worked example (our own): The line y = 3x − 1 meets the curve y = 2x² + x − 5. Show that the x-coordinates of the points of intersection satisfy x² − x − 2 = 0.
Loses marks
3x − 1 = 2x² + x − 5
so x² − x − 2 = 0
Earns the marks
3x − 1 = 2x² + x − 5
0 = 2x² − 2x − 4
0 = 2(x² − x − 2)
x² − x − 2 = 0, as required
Why: In a "show that" the answer is given, so the marks are for every step in between, and the final line must match the printed answer exactly (including "= 0").
#2Inverse and composite functions: domain left out, fg and gf mixed up
What examiners saw: Finding f⁻¹ algebraically is usually fine; the mark that goes is the domain of the inverse. Examiners also see fg(x) and gf(x) swapped, and "inverse" confused with the reciprocal or with a reflection in an axis.
Fix: Write the domain of f⁻¹ every time (it is the range of f). For fg(x), apply g first. For the graph of f⁻¹, reflect in y = x.
Worked example (our own): f(x) = 2x + 3 with domain x ≥ 1. Find f⁻¹(x) and state its domain.
Loses marks
y = 2x + 3 ⇒ x = (y − 3)/2
f⁻¹(x) = (x − 3)/2 (domain left out)
Earns the marks
y = 2x + 3 ⇒ x = (y − 3)/2, so f⁻¹(x) = (x − 3)/2
Range of f: f(1) = 5 and f is increasing, so f(x) ≥ 5
Domain of f⁻¹ = range of f: x ≥ 5
Why: The domain of the inverse is the range of the original function. Examiners withhold the final mark when it is missing.
#3Modelling: model not written out, limitation not in context
What examiners saw: Constants are found correctly but the final model is not stated, units are left off, and "limitation" answers are generic or confuse a limitation of the model with a limit on a value.
Fix: Finish with the full equation of the model. Give limitations and interpretations using the context's words and units.
Worked example (our own): A drink cools according to T = 20 + 60e⁻ᵏᵗ (T in °C, t in minutes). When t = 10, T = 50. Find the model and give one limitation.
Limitation: it assumes the room stays at 20 °C; the drink can never cool below 20 °C in this model.
Why: If a question says "find the model", the final line must be the complete equation. A limitation must be about this model in this context, not a general comment.
What examiners saw: Statistics answers are often inaccurate because a rounded intermediate value (such as a mean) was reused, or because answers were truncated (0.0147…→0.0147) instead of rounded. Accuracy instructions ("3 decimal places") are also missed.
Fix: Store calculator values in memory, round only at the end, and round (don't chop). Re-read the accuracy the question asks for.
Worked example (our own): Five values have Σx = 76 and Σx² = 1210. Find the standard deviation.
Loses marks
mean = 15.2 ≈ 15
variance = 1210/5 − 15² = 242 − 225 = 17
sd = 4.12
Earns the marks
mean = 76/5 = 15.2 (keep the exact value)
variance = 1210/5 − 15.2² = 242 − 231.04 = 10.96
sd = √10.96 = 3.31 (3 s.f.)
Why: Rounding the mean before using it changed the answer from 3.31 to 4.12. Keep full calculator values until the final line.
#5Proof: "squares are always positive" and no concluding statement
What examiners saw: In "prove for all real x" questions, completing the square is the right idea, but many write that a square is always positive (it can be zero) and stop without a conclusion. Trying a few numbers is not a proof.
Fix: Use (…)² ≥ 0, carry the inequality through, and end with a sentence restating what has been proved.
Worked example (our own): Prove that x² − 6x + 10 > 0 for all real x.
Loses marks
x² − 6x + 10 = (x − 3)² + 1
"Squares are always positive, so it is positive."
Earns the marks
x² − 6x + 10 = (x − 3)² + 1
(x − 3)² ≥ 0 for all real x (it can equal 0, when x = 3)
so (x − 3)² + 1 ≥ 1 > 0
Hence x² − 6x + 10 > 0 for all real x.
Why: A square is never negative, but it can be zero. Use ≥ 0, then finish with a sentence that says what you have proved.
What examiners saw: The method is well known, but minus signs are dropped when integrating e⁻ˣ, sin x or cos x, and double negatives are not simplified. Some choose u the wrong way round and end up with a harder integral.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#7R cos(θ − α): wrong ratio for tan α and calculator in the wrong mode
What examiners saw: Harmonic-form questions lose marks through tan α taken the wrong way up and through radians used when the interval is in degrees (or the reverse). Later parts that should use the R-form are often restarted from scratch.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#8Graph transformations: direction and scale factor inside the bracket
What examiners saw: Single transformations are mostly fine; f(2x) treated as ×2 on x (it halves x), f(x + a) moved the wrong way, and multi-step transformations guessed rather than done one step at a time.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#9Mechanics: too many significant figures after using g = 9.8
What examiners saw: Final answers given to 4 or more significant figures (or as fractions) after substituting g = 9.8 lose the accuracy mark, and units are often missing.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#12Normal distribution: continuity correction used on a continuous variable
What examiners saw: Continuity corrections are applied where the variable is already continuous, units are not converted (minutes vs seconds), and the wrong tail is used in inverse-normal questions.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#13Binomial expansion (rational n): factor not raised to the power, validity not stated
What examiners saw: Taking out a factor is common, but the factor is not raised to the power n, and the range of validity is left out or not compared with the value asked about.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
What examiners saw: Values are usually correct, but the conclusion misses continuity, misstates it ("x is continuous"), or never says a root lies in the interval. Some forget to rearrange to the form = 0 first.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#15Moments: wrong distances and forces missing from the diagram
What examiners saw: Force diagrams with a reaction drawn vertically instead of perpendicular to the rod, extra or missing forces (including the rod's own weight), and distances measured from the wrong point.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
How often each topic appeared, and for how many marks
Every question in the papers we read, matched to a topic. Numbers are marks (from the published mark schemes; a question that tests two topics has its marks split). Hover or tap a cell to see the questions.
Confidence: high for the series shown — every question was read and mapped by hand. "Series" = how many of the 2 series examined the topic.
Paper by paper
Every paper we analysed, question by question
Topics are ours (matched from each report's question-by-question comments). We don't reproduce the questions: open the official paper from our past-paper page.
Top 10 mistakes examiners see in Edexcel A Level Maths
A one-page PDF of the ten most common mark-losing mistakes and how to avoid them. Print it and stick it inside your revision folder.
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Sources
Where this comes from
We read all four 9MA0 examiner reports for June 2024 and June 2025 in full, and matched every question to our topics using the published mark schemes for the marks. Earlier reports (2022, 2023) exist but could not be opened from our tools, so trends here cover two series.
What do examiners say students get wrong in Edexcel A Level Maths?
The most repeated points are: "Show that"; Inverse and composite functions; Modelling. Each one on this page has the fix and, where free, a worked example showing the wrong and right method.
Which Edexcel A Level Maths topics come up most?
In the material we analysed, the biggest areas were Algebra and functions, Differentiation, Integration and differential equations.
Is this a prediction of the June 2027 paper?
No one outside the exam board knows what will be on the next paper. The "focus" list is an informed prediction from how often topics appeared and how weakly they were answered; it is not a guarantee, so revise the whole specification.
Where does this information come from?
We read 8 Pearson Edexcel examiner reports (June 2024, June 2025) in full, summarised them in our own words and linked each point to the original.
A Level Math Revision