What the examiners said about IB Maths AA HL — and exactly what to do about it
Built from two of the IB's own AA HL subject reports (May 2024 TZ2 and November 2025 TZ3), read in full, covering Papers 1, 2 and 3 and the exploration. Where a mistake is about content that SL and HL share, we also cite the five AA SL reports we read (May 2024 TZ2 to November 2025 TZ3) and label them as SL. The reports were supplied by the site owner; the IB makes subject reports available to IB World Schools through its Programme Resource Centre. With only two HL sessions, treat the HL-only points as lower confidence. Everything here is in our own words: we do not reproduce the reports or any exam question, and every worked example is our own. The question topics are our own matching from the reports' comments; we show no marks per question because we did not use the markschemes.
Summaries are in our own words with links to the originals. Predictions are informed guesses, not a guarantee. You'll meet these notes as you revise too: under practice questions, inside mark schemes, in your AI marking and in “What to do next”.
Ranked for May 2027
What to focus on for May 2027
November 2026 candidates can use the same list. Ranked by how often each area appeared and how weakly it was answered.
Informed prediction, not a guarantee: any topic on the specification can be examined.
1
Calculus: volumes about the y-axis, differential equations, pdfs
The largest block of questions in both HL sessions; volumes about the y-axis, integrating-factor equations and pdf calculations are named as difficult in both.
Describing transformations and graphs of related functions were among the least successful Paper 1 parts in November 2025; hidden quadratics and log laws recur.
The 10 mistakes that cost the most marks (and 8 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.
#1Accuracy: early rounding, 2 s.f. answers and ignoring the stated number of decimal places
What examiners saw: Both HL reports say early rounding still costs marks on Paper 2 (a rounded time reused to find an acceleration, a rounded radius in a related-rates part, premature rounding in a normal-distribution part). Paper 3 answers were rounded to 2 s.f., or not to the number of decimal places the question asked for. The AA SL reports make the same point every session.
Fix: Store full values and round once, at the end: exact or 3 s.f. unless told otherwise. When a question says "to 6 decimal places", do exactly that. For a given answer, show your value to more figures than the printed one.
Worked example (our own): An account grows as A = 800e^(0.042t). Find t when A = 1500, then the value 10 years after that.
#2"Show that" and proofs: verifying, working backwards or working on both sides
What examiners saw: HL candidates verified roots instead of showing a result, wrote circular arguments, worked on both sides of an identity at once, offered dubious steps to land on a printed answer, stated a > 0 without a reason, and on Paper 3 worked back from the answer given or checked it by substitution. Crossed-out working is not marked, so a rejected solution needs a written reason instead.
Fix: Start from one side (or from the given facts) and move to the result line by line, with a reason for any condition such as a > 0. Give the reason for rejecting a solution in words. Never start from the printed answer.
Worked example (our own): Show that (1 − cos 2x)/sin 2x ≡ tan x.
Loses marks
(1 − cos 2x)/sin 2x = tan x
1 − cos 2x = tan x sin 2x … (both sides changed at once)
Earns the marks
LHS = (1 − (1 − 2sin²x))/(2 sin x cos x)
= 2sin²x/(2 sin x cos x)
= sin x/cos x = tan x = RHS
Why: Treating the identity as an equation assumes what you are proving. Transform one side until it becomes the other.
#3Slow algebra on Paper 2 where the GDC is expected
What examiners saw: Both HL reports: areas, accelerations, medians and systems of equations were done by hand, often with errors; expanding a square to integrate by hand for a volume wasted time; analytic attempts at trigonometric equations stalled; and few used the GDC for a 3 × 3 system. The recommendation is to teach when and how to use the GDC in every topic.
Fix: On Paper 2, write the equation or integral in mathematical notation, then evaluate it on the GDC. Use analytic methods only where the question asks for an exact answer or says "show" or "deduce".
Worked example (our own): X has pdf f(x) = (4/27)x²(3 − x) for 0 ≤ x ≤ 3. Find the median of X.
Loses marks
(4/27)(m³ − m⁴/4) = ½ ⇒ 8m³ − 2m⁴ = 27 … (quartic attempted by hand, abandoned)
Earns the marks
∫₀ᵐ (4/27)x²(3 − x) dx = 0.5
Solve on the GDC for 0 ≤ m ≤ 3: m = 1.84 (3 s.f.)
Why: The equation is correct but a quartic is not meant to be solved by hand on Paper 2. Write it down, then let the GDC solve it in the valid interval.
#4Arithmetic with limits, fractions and simultaneous equations on Paper 1
What examiners saw: The November 2025 HL report asks for more care substituting limits into integrals and solving simultaneous equations by hand, and notes that errors adding fractions cost most candidates the last marks of an area question. The AA SL reports repeat the point about brackets and non-calculator arithmetic every session.
Fix: Write F(upper) − F(lower) with each value in brackets before simplifying. Keep fractions as fractions. Check a simultaneous-equation solution by substituting back.
Worked example (our own): Find the area enclosed by y = 4 − x² and y = x + 2.
Loses marks
Limits x = −2 and x = 1
[2x − x²/2 − x³/3] = 7/6 − 10/3 = −13/6, so area 13/6
Earns the marks
4 − x² = x + 2 ⇒ x² + x − 2 = 0 ⇒ x = −2 or 1
Area = ∫₋₂¹ (2 − x − x²) dx = [2x − x²/2 − x³/3]₋₂¹
= (7/6) − (−10/3) = 7/6 + 20/6 = 9/2
Why: F(−2) = −10/3 must be subtracted, so its sign flips. Brackets round each evaluated limit prevent the slip.
#5Trigonometric equations: missing solutions (obtuse, general or divided away)
What examiners saw: HL candidates missed a second (often obtuse) solution, picked the wrong GDC solution for the interval, expanded a compound angle instead of solving directly, wrote incorrect general solutions, and on Paper 3 did not know exact inverse-trig values. The SL reports record the same pattern.
Fix: Sketch the function over the whole interval and count intersections before solving. Factorise rather than divide by a trig function (dividing loses the solutions where it is zero).
Worked example (our own): Solve sin 2x = cos x for 0 ≤ x ≤ π.
Loses marks
2 sin x cos x = cos x ⇒ 2 sin x = 1 (dividing by cos x)
x = π/6
Earns the marks
2 sin x cos x − cos x = 0 ⇒ cos x(2 sin x − 1) = 0
cos x = 0 ⇒ x = π/2
sin x = ½ ⇒ x = π/6 or 5π/6
Why: Dividing by cos x throws away x = π/2, and sin x = ½ has a second solution in the interval.
#6Proof by induction: weak structure and "let n = k"
What examiners saw: Both HL reports ask for induction to be set out as a formal proof. Candidates wrote "let n = k" or "assume n = k" instead of assuming the statement is true for n = k, started at the wrong base case, could not set up the inductive step so that the assumption is used, and skipped stages when deriving an expression. November 2025 Paper 3 found that applying induction in an unfamiliar setting was hard.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#7"Hence", "deduce" and "exact": using the wrong method
What examiners saw: The HL reports ask for command terms to be taught explicitly: "deduce" needs an analytic argument, "hence" must use the previous part, and an exact answer is rarely found on a GDC. November 2025 Paper 3 candidates used technology for points whose coordinates were exact, and the report asks students to look for the connections between parts.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#8Volumes of revolution and areas: wrong axis, missing π or square, wrong limits
What examiners saw: Rotating about the y-axis caused trouble in both HL sessions: π left out, the function not squared, limits in x instead of y, the x-axis formula used, and time wasted expanding a square to integrate by hand. For areas and probabilities, zero was used as a lower bound where it did not apply.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#9Differential equations: integrating factor and the constant of integration
What examiners saw: Few November 2025 candidates were ready for an integrating-factor equation. In May 2024 many forgot the constant, did not use the boundary condition to find it (or to show it was zero), made sign errors in the integrating factor, or did not recognise ∫ f′(x)/f(x) dx = ln|f(x)| + c.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#10Continuous random variables: mode, median and expectation from a pdf
What examiners saw: In both HL sessions pdf questions lost marks: the mode found by differentiating instead of reading the graph (or not recognised as the x-value of the maximum), the median found algebraically when the GDC was quicker, wrong bounds for part of the domain, and very few able to set up an expectation. Comparing a probability with 0.5 to place the median was rarely used.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#11Discrete probability: independence assumed, E(X²) and Var misused
What examiners saw: November 2025: many mishandled P(A ∩ B) and the conditional probability that followed, gave the sum-to-1 condition when a range of values of a parameter was asked, squared the probabilities to find E(X²), and did not use Var(a − X) = Var(X). May 2024: choosing one group of people fixed the other (a combinations point missed). The SL reports show the same probability errors.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#12Vectors: skew lines without the non-parallel check, and planes
What examiners saw: November 2025: many did not show that the lines were not parallel before concluding they were skew, made errors solving the simultaneous equations (often with scattered working), and did not give a plane's equation with integer coefficients. May 2024: the relationship between planes was often misread; the report recommends diagrams.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#13Graphs and transformations: describing a rational function, and graphs of [f(x)]²
What examiners saw: November 2025: few found the vertical stretch when describing a rational function as a transformation of 1/x, sketches of y = [f(x)]² showed the wrong maximum, and an inequality answer omitted its upper bound. May 2024: candidates used algebra where the given graph answered the question. The SL reports show the same difficulty describing transformations.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#14Complex numbers and polynomials: conjugate roots, all the roots, general solutions
What examiners saw: May 2024: many knew the conjugate root was needed but did not use all the roots in the sum and product relations. November 2025: manipulation of a number in cis form was unconvincing and general solutions of a trigonometric equation were often wrong; on Paper 2, candidates had to discard an inappropriate root.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#15Logs and exponentials: hidden quadratics and misapplied log laws
What examiners saw: May 2024: candidates who did not spot a hidden quadratic took logs of a sum. November 2025: log(10x)³ was misread, so the power was applied to only part of the argument. The SL reports show the same log-law errors every session.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
What examiners saw: Fewer HL candidates than before, but still some, worked a kinematics question in degrees and scored nothing for it; the report advises radian mode for trigonometric functions in calculus. It remains a regular loss in the SL reports.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#17Not using the given information and earlier parts on Paper 3
What examiners saw: Both Paper 3 reports: many candidates did not follow a method the question specified, did not look for the connections between parts, did not work systematically through cases with several solutions, or worked backwards from an answer given. Graph paper in scanned scripts is hard to mark.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#18Exploration (IA): research reports and mathematics beyond what you can explain
What examiners saw: Both HL IA sections: explorations that paraphrase published work (well-known topics transcribed from books or websites) cannot reach the higher levels; university-level topics are often misunderstood; long appendices hold steps the reader needs; reflection is descriptive rather than critical; and HL work must go beyond SL-level mathematics to be credited as sophisticated. Sources and any AI use must be acknowledged where they are used.
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. Columns marked * count questions (q) because the marks could not be verified from the mark scheme. Hover or tap a cell to see the questions.
4q (Paper 1 (TZ2) Q2, Paper 1 (TZ2) Q7, Paper 1 (TZ2) Q10, Paper 1 (TZ2) Q12)
9q (Paper 1 (TZ3) Q1, Paper 1 (TZ3) Q4, Paper 1 (TZ3) Q11, Paper 2 (TZ3) Q7, Paper 2 (TZ3) Q9, Paper 2 (TZ3) Q10, Paper 2 (TZ3) Q12, Paper 3 (TZ3) Q1, Paper 3 (TZ3) Q2)
5q (Paper 1 (TZ2) Q3, Paper 1 (TZ2) Q4, Paper 1 (TZ2) Q5, Paper 2 (TZ2) Q9, Paper 3 (TZ2) Q2)
3q (Paper 1 (TZ3) Q3, Paper 1 (TZ3) Q5, Paper 2 (TZ3) Q6)
2/2
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.
Separable first-order DEs; Integration by substitution
Q2
Discriminant & the number of real roots; Normal distribution (probability lookups)
Pro
Your mistakes vs the examiners' hot-spots
We set the topics in My mistakes and your practice scores against this page's mistakes library and focus list, and rank where they overlap, with a practice link for each.
Free account: how many of your notebook entries match, and the top one. Pro: the full ranked list, your focus areas and your risk list.
A one-page PDF of the 10 most common mark-losing mistakes and how to avoid them. Print it and stick it inside your revision folder.
Sources
Where this comes from
Built from two of the IB's own AA HL subject reports (May 2024 TZ2 and November 2025 TZ3), read in full, covering Papers 1, 2 and 3 and the exploration. Where a mistake is about content that SL and HL share, we also cite the five AA SL reports we read (May 2024 TZ2 to November 2025 TZ3) and label them as SL. The reports were supplied by the site owner; the IB makes subject reports available to IB World Schools through its Programme Resource Centre. With only two HL sessions, treat the HL-only points as lower confidence. Everything here is in our own words: we do not reproduce the reports or any exam question, and every worked example is our own. The question topics are our own matching from the reports' comments; we show no marks per question because we did not use the markschemes.
What do examiners say students get wrong in IB Maths AA HL?
The most repeated points are: Accuracy; "Show that" and proofs; Slow algebra on Paper 2 where the GDC is expected. Each one on this page has the fix and, where free, a worked example showing the wrong and right method.
Which IB Maths AA HL topics come up most?
In the material we analysed, the biggest areas were Calculus, Number and algebra, Statistics and probability.
Is this a prediction of the May 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 2 International Baccalaureate examiner reports (May 2024 TZ2, November 2025 TZ3) in full, summarised them in our own words and linked each point to the original.
IB Math Revision