What the examiners said about IB Maths AA SL — and exactly what to do about it
Built from five of the IB's own AA SL subject reports (May 2024 TZ2, November 2024 TZ2, May 2025 TZ1 and TZ2, November 2025 TZ3), read in full. They were supplied by the site owner; the IB makes subject reports available to IB World Schools through its Programme Resource Centre. We have not seen every timezone's report for these sessions. 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 in context: kinematics, integration with a boundary condition, optimisation
Calculus questions appear in every paper we mapped, and kinematics or integrating with a boundary condition is named as difficult in every session (maximum speed, distance, fastest rate, "closest").
High confidenceAA SL reports: M24 TZ2, N24 TZ2, M25 TZ1, M25 TZ2, N25 TZ3Difficult-areas lists on both papers
Probability and distributions: conditional probability, binomial inequalities, normal bounds
Probability parts were left blank or badly answered in four of five sessions; the reports single out assuming independence, conditional probability with complements and binomial/normal set-up.
Functions: rational functions, transformations, inverses and logs
Rational functions and transformations recur on Paper 1 every session, with marks lost on asymptote notation, incomplete transformation descriptions and log laws.
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: 2 s.f. answers, early rounding and ignored accuracy instructions
What examiners saw: Named in every Paper 2 report we read. Candidates gave final answers to 2 significant figures, rounded an intermediate value (a time, a length, an angle) and carried it forward, so that even a part asking for 4 significant figures came out wrong, or ignored a question that asked for a percentage or a whole number.
Fix: Keep full calculator values (store them) until the very last line. Give final answers exactly or to 3 s.f. unless the question says otherwise, and when a given answer has more figures, show your value to more figures than that before rounding.
Worked example (our own): A population grows as P = 1200e^(0.035t). Find t when P = 2000, then the population 5 years later.
Loses marks
e^(0.035t) = 5/3 ⇒ t ≈ 15
P(20) = 1200e^(0.7) = 2416.5…, so 2420
Earns the marks
t = ln(5/3)/0.035 = 14.595… (keep this in the GDC)
#2"Show that": substituting or working back from the given answer
What examiners saw: Every session's reports return to this. Candidates plugged the printed value in to check it, solved the printed equation instead of deriving it, worked backwards, cancelled on both sides like scratch work, or tested a few numbers instead of proving a general result. None of these earn the marks, and an extraneous solution simply crossed out (with no reason) was also penalised.
Fix: Start from the information in the question and write every step, left-hand side to right-hand side, until you reach the printed result, then say "as required". If you reject a value, give the reason in words.
Worked example (our own): The equation x² + kx + 9 = 0, where k > 0, has equal roots. Show that k = 6.
Loses marks
Substitute k = 6: x² + 6x + 9 = (x + 3)², which has equal roots ✓
Earns the marks
Equal roots ⇒ discriminant = 0: k² − 4(1)(9) = 0
k² = 36 ⇒ k = ±6
k > 0, so k = −6 is rejected and k = 6, as required
Why: Substituting the printed value only checks it; it does not show that k must be 6. Start from the condition and derive the value, giving a reason for rejecting −6.
#3Missing brackets and arithmetic slips on Paper 1 (subtracting, squaring, simplifying)
What examiners saw: The Paper 1 reports say candidates often understood the method but lost the marks in the algebra: brackets left off when subtracting a second expression or squaring a negative, a quotient-rule numerator without brackets, a square expanded without its middle term, and fraction or decimal arithmetic that went wrong without a calculator.
Fix: Put brackets round every expression you subtract or square, and expand them on a separate line. Work in fractions rather than long decimals on Paper 1, and simplify fully (integers as integers, surds simplified).
Worked example (our own): Simplify (2n + 1)² − (2n − 1)².
Loses marks
4n² + 1 − 4n² − 4n + 1
= 2 − 4n
Earns the marks
(4n² + 4n + 1) − (4n² − 4n + 1)
= 4n² + 4n + 1 − 4n² + 4n − 1
= 8n
Why: Squaring needs the middle term, and the whole second expansion must be subtracted: brackets make both of these visible.
#4Doing by hand what the GDC should do on Paper 2, and not writing what you solved
What examiners saw: Candidates spent time finding quartiles, intersections, roots, means from frequency tables and derivatives at a point by hand, often wrongly; analytic attempts at intersections even lost marks. Others wrote only "using my GDC" or calculator syntax. Examiners want the equation, integral or distribution written in maths notation, then the answer.
Fix: On Paper 2, use the GDC for roots, intersections, statistics, numerical derivatives and integrals. Write the equation or integral you entered in normal notation, then the value. Treat a 2 or 3 mark part as a sign that a quick GDC method is expected.
Worked example (our own): Find the x-coordinates of the points where y = ln(x + 2) meets y = x² − 1.
Loses marks
ln(x + 2) = x² − 1 ⇒ x + 2 = e^(x² − 1) … (algebra that goes nowhere)
x = 1.5 (no working)
Earns the marks
ln(x + 2) = x² − 1 (solved graphically on the GDC)
x = −1 or x = 1.50 (3 s.f.)
Why: This equation has no algebraic solution. Write the equation you solved, then read both intersections from the GDC; a bare, rounded value earns nothing if it is wrong.
#5Answer in the wrong form: asymptotes not as equations, coordinates vs values, unfinished answers
What examiners saw: A recurring loss of easy marks: an asymptote written as "HA = …", "y ≠ …" or just a number instead of an equation y = …; coordinates given when values of x were asked for (or the reverse); an axis of symmetry not written as x = …; interval answers in the wrong notation; and answers left unfinished, such as an unevaluated logarithm, a fraction of decimals or a surd that still simplifies.
Fix: Lines are equations: write y = … or x = …. Give exactly what the question names (a value, a point, an interval). Finish the arithmetic: integers as integers, fractions with integer numerators and denominators in lowest terms.
Worked example (our own): State the asymptotes of y = (4x + 1)/(2x − 6), and evaluate log₃81.
Loses marks
HA = 2, VA = 3
log₃81
Earns the marks
Horizontal asymptote: y = 2
Vertical asymptote: x = 3
log₃81 = 4
Why: An asymptote is a line, so the answer is its equation. A value that simplifies to an integer must be simplified.
What examiners saw: Candidates redid a "hence" part from scratch (for example a messy substitution instead of the result just shown), missed that an earlier part was the key to the next, or never used a given graph. Reports also advise trying later parts even after getting stuck, because the information needed is often given.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#7Kinematics: speed vs velocity, change of direction, distance vs displacement
What examiners saw: Seen in every session. Candidates gave the maximum velocity when the maximum speed was asked, found maximum speed or acceleration by setting a derivative to zero instead of reading the graph and endpoints, did not link a change of direction to v = 0, used the GDC in degrees, and integrated v (displacement) when distance was asked.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#8Probability: assuming independence, and conditional probability with complements
What examiners saw: Candidates multiplied probabilities for events that were not independent, found a union when an intersection was asked, used the independence formulas to work backwards, mishandled P(A | B′), misread "more than" in a discrete setting, and left answers as unsimplified fractions of decimals. When writing the conditional formula, generic P(A | B) with no reference to the context was not credited.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#9Binomial and normal: "at least", inequalities, rounding bounds and which distribution
What examiners saw: Recurring errors: P(X ≥ 1) written as 1 − P(X ≤ 1); forgetting to reverse an inequality after dividing by a negative logarithm; an off-by-one slip when turning a strict inequality for a whole-number variable into a cumulative probability; a normal probability found for a single value instead of between the rounding bounds; the binomial used where the normal was needed (or the reverse); an inverse-normal value taken from the wrong tail; and μ and σ from two probabilities solved by hand.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#10GDC in the wrong angle mode, and degrees in radian formulas
What examiners saw: Reported in four of the five sessions: kinematics and trigonometric models worked in degree mode, the sector-area formula used with the angle in degrees, the GDC's simultaneous-equation solver used in the wrong mode, and a bearing question done in radians.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#11Trigonometric equations: one solution only, and exact values not known
What examiners saw: Candidates found the first solution and stopped (missing the second angle in the interval), gave the value of sin x instead of x, did not know exact values such as tan⁻¹1, sin(5π/6), cos π and cos 60°, mistook the period of tan, and on Paper 2 spent time rearranging by hand instead of solving graphically.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#12Integration: missing +C, substituting into the derivative, and area limits
What examiners saw: Given a derivative and a point, candidates substituted the point into the derivative, differentiated instead of integrating, or dropped the constant. Integrating e^(kx) without the 1/k, not recognising ∫ 1/x dx = ln x, not writing the final function, and substituting only one limit in an area were all reported.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#13Transformations and inverses: incomplete descriptions and f⁻¹ notation
What examiners saw: Candidates described only one of two transformations, gave a translation in the wrong direction, mishandled a vertical stretch (multiplying a function by a constant), misapplied log laws before transforming, and did not recognise f⁻¹ notation or that the domain of f⁻¹ is the range of f.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#14Modelling in context: not setting up the expression, and answers that ignore the context
What examiners saw: Candidates did not recognise "closest" or "fastest" as an optimisation, solved h′(t) = 0 when the fastest rate needed h″(t) = 0, left units inside algebraic expressions, gave a time when a year was asked, forgot that a population was in millions, rounded a number of rows the wrong way, and kept two solutions when the context allowed one.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#15Sequences: term vs sum, counting n, and spotting the sequence
What examiners saw: Candidates used Sₙ when a term (or a sum of two terms) was needed, used n = 5 where the 6th term was meant, did not see that a pattern formed an arithmetic series, missed that a bouncing distance counts up and down, and found the median of a finite geometric sequence at a non-existent "5.5th" term.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#16Proof: testing a few values instead of proving the general case
What examiners saw: In a "show that … is a multiple of" question, a large number of candidates substituted several integers and stopped, which earned nothing. Similar: computing two specific terms and calling it a "show that".
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#17Binomial expansion: the coefficient inside the bracket is not raised to the power
What examiners saw: Reported in two sessions: (2x)⁶ written as 2x⁶, brackets omitted round the 2x, the whole term given when only the coefficient was asked, and a second valid value of k missed.
Pro: the fix and a worked example (wrong vs right method) for this mistake are in Pro. See plans
#18Exploration (IA): regression without justification, and reflection only at the end
What examiners saw: Every IA section we read makes the same points: statistics and regression dominate, often with a model chosen from software output or R² alone, correlation treated as causation, behaviour outside the data ignored, and mathematics beyond the course used without understanding. Reflection is the weakest criterion because it is a summary at the end rather than critical thinking that drives the next step. Communication loses marks for computer notation (*, ^), missing ≈ signs and small, unlabelled graphs.
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) Q8, Paper 2 (TZ2) Q2, Paper 2 (TZ2) Q5, Paper 2 (TZ2) Q8)
4q (Paper 1 (TZ2) Q7, Paper 1 (TZ2) Q9, Paper 2 (TZ2) Q3, Paper 2 (TZ2) Q9)
14q (Paper 1 (TZ1) Q2, Paper 1 (TZ1) Q4, Paper 1 (TZ1) Q7, Paper 1 (TZ1) Q9, Paper 2 (TZ1) Q1, Paper 2 (TZ1) Q4, Paper 2 (TZ1) Q6, Paper 1 (TZ2) Q1, Paper 1 (TZ2) Q2, Paper 1 (TZ2) Q6, Paper 1 (TZ2) Q8, Paper 1 (TZ2) Q9, Paper 2 (TZ2) Q3, Paper 2 (TZ2) Q5)
4q (Paper 1 (TZ3) Q2, Paper 1 (TZ3) Q8, Paper 1 (TZ3) Q9, Paper 2 (TZ3) Q9)
3q (Paper 1 (TZ2) Q2, Paper 1 (TZ2) Q7, Paper 2 (TZ2) Q9)
5q (Paper 1 (TZ2) Q2, Paper 1 (TZ2) Q5, Paper 1 (TZ2) Q9, Paper 2 (TZ2) Q5, Paper 2 (TZ2) Q9)
9q (Paper 1 (TZ1) Q9, Paper 2 (TZ1) Q2, Paper 2 (TZ1) Q3, Paper 2 (TZ1) Q8, Paper 1 (TZ2) Q4, Paper 1 (TZ2) Q8, Paper 2 (TZ2) Q2, Paper 2 (TZ2) Q6, Paper 2 (TZ2) Q7)
5q (Paper 1 (TZ3) Q7, Paper 2 (TZ3) Q2, Paper 2 (TZ3) Q3, Paper 2 (TZ3) Q5, Paper 2 (TZ3) Q8)
3q (Paper 1 (TZ2) Q4, Paper 1 (TZ2) Q6, Paper 2 (TZ2) Q2)
7q (Paper 1 (TZ1) Q1, Paper 1 (TZ1) Q3, Paper 1 (TZ1) Q6, Paper 2 (TZ1) Q1, Paper 2 (TZ1) Q8, Paper 2 (TZ2) Q4, Paper 2 (TZ2) Q9)
4q (Paper 1 (TZ3) Q3, Paper 1 (TZ3) Q6, Paper 2 (TZ3) Q7, Paper 2 (TZ3) Q9)
4/4
Confidence: high for the series shown — every question was read and mapped by hand. "Series" = how many of the 4 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.
Least-squares regression line; Central tendency (mean/median/mode)
Q4
Logarithmic graphs & solving log equations
Q5
Kinematics: displacement, velocity, acceleration
Q6
Discrete random variables & E(X)
Q7
Normal distribution (probability lookups); Discrete random variables & E(X)
Q8
Optimisation in context
Q9
Sine rule; Cosine rule
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 five of the IB's own AA SL subject reports (May 2024 TZ2, November 2024 TZ2, May 2025 TZ1 and TZ2, November 2025 TZ3), read in full. They were supplied by the site owner; the IB makes subject reports available to IB World Schools through its Programme Resource Centre. We have not seen every timezone's report for these sessions. 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 SL?
The most repeated points are: Accuracy; "Show that"; Missing brackets and arithmetic slips on Paper 1 (subtracting, squaring, simplifying). Each one on this page has the fix and, where free, a worked example showing the wrong and right method.
Which IB Maths AA SL topics come up most?
In the material we analysed, the biggest areas were Calculus, Geometry and trigonometry, Functions.
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 5 International Baccalaureate examiner reports (May 2024 TZ2, November 2024 TZ2, May 2025 TZ1, May 2025 TZ2, November 2025 TZ3) in full, summarised them in our own words and linked each point to the original.
IB Math Revision