The list is now “complete”, in the sense that it includes all the errors of which we are aware. (We have given the earlier exams only a very, very quick scan.) We will update and correct the list, whenever anything is brought to our attention, and of course when new exams appear.
2023 EXAM 2 (No exam yet – discussed here)
MCQ6 The pseudocode is very poorly written, and will not print out what is indicated.
QB(1)(b) (Discussed here) Given VCAA’s use of and multiple misunderstanding of the term “smooth”, it can no longer be taken for granted that “meet smoothly” means simply that the function values and derivatives match at the endpoints.
QB(2)(a)(b) The writers use “root” to mean “solution”.
Q2(d) Part (ii) asks for the polar equation of “the ray” drawn in (i). This equation, however, will necessarily exclude the ray’s starting point, which would legitimately and naturally be included in the answer to (i).
QB(2)(f)(i) The specification of A and B is not unique (and is poor preparation for (f)(ii)).
QB(3)(a) Rotating a curve does not give a “solid”.
QB(3)(b)(i) The specification of a, b, A and B is not unique.
QB(4)(e)(ii) The “maximum number of fish that could be supported” is not properly defined, and may not mean what VCAA thinks it means. In general it is, at best, unwise to to use “maximum” to refer to such an equilibrium solution.
QB(5)(b)(e) It is not clear why such distance questions are examinable, since there is zero reference to them in the study design. If they are examinable, it is not clear why the relevant formulas are not included on the formula sheet. Also “shortest distance” should simply be “distance”.
QB(5)(d) Asking for “an equation [singular] of the line in parametric form” is inaccurate, and may or may not suggest that a vector equation is a desired/permitted answer.
QB(6)(h) Famously, the graph labels were interchanged.
2023 EXAM 1 (No exam yet – discussed here)
Q4. Asking for an answer in the form -π√a/b with a and b positive integers is not good form, with no unique answer.
Q6(b) A very poorly posed question. There are infinitely many possible answers, and a second and presumably unintended answer is easily findable.
Q7 An “open hollow surface” is not a mathematical thing. It is appalling wording and makes the question of “surface area” ambiguous. The specification of the form of the answer as π(a√b/c – d) is highly non-unique and very bad form.
We are not aware of any errors on this exam.
We are not aware of any errors on this exam.
MCQ1 (added 06/04/23 – discussed here) Flat out wrong. Quantified statements do not have contrapositives.
MCQ2 (added 06/04/23 – discussed here) VCAA fails to follow its own conventions.
Q2 (added 06/04/23 – discussed here) A completely screwed induction question.
Q4 (added 06/04/23 – discussed here) A proof by contradiction that should be done directly.
Q6 (added 06/04/23) Rotated curves sweep out surfaces, not solids.
Q7 (added 06/04/23) The exact same issue as Q6.
Q10 (added 06/04/23 – discussed here) A badly flawed logistic population question. Part (a) is unanswerable, and (c) is not asking what VCAA thinks it is asking.
MCQ4 (added 10/11/22) – discussed here. There is simply no correct answer. A shocking error, after having made basically the same error the previous year (and refusing to own up to it). (06/04/23) The report simply pretends the error did not occur.
MCQ19 (added 10/11/22) – discussed here. The population mean is given rather than the required sample mean. The question can be done in some mechanical manner, but is fundamentally meaningless and pointless.
QB4(d) (added 10/11/22) The question is badly ambiguous. In asking “how far does the ball travel” it is unclear whether arc length or straight-line distance is required.
QB6(f) (added 10/11/22) – discussed here. A mess, since the required independence of random variables has not been declared. What was intended is unclear, leading to two different answers, both arguably reasonable. (06/04/23) The report simply pretends the error did not occur.
Q3(b) (added 11/11/22 – discussed here) The statement on “the mean time taken to dispense 25 cups of coffee” is unambiguous, and simply does not declare what was intended. (06/04/23) The report simply pretends the error did not occur.
Q6(b)(i) (added 10/11/22) There is a pretty serious ambiguity, since the vectors can also be expressed without any reference to y.
Q6(b)(ii) (added 14/12/22) The “vector scalar (dot) product” is not a thing.
Q7 (added 10/11/22) There are multiple answers of the required form.
Q10(b) (added 10/11/22) Asking for the answer in the form (a – √b)/c with a, b and c real is absurd. Presumably it was intended that a, b and c be integers, which would still have been flawed, but somewhat reasonable. (01/04/23) Worse, as has just been pointed out to us, rotating a graph does not create a solid of revolution: it creates a surface of revolution. This issue also appears here.
(31/10/23) We are not aware of any errors on this exam (except ours).
QB5 (Added 28/10/23, discussed here) To maintain the desired inequality in part (e), one must round the answer up, to 0.5027. The exam report rounds down, to 0.5026. (29/10/23) The report uses the wrong notation in part (a): should be used instead of . (31/10/23) My informants tell me that this question was added in error: the question asks for the null hypothesis to not be rejected, meaning we want to ensure p > 0.5, and so we need to round down. See here.
Q6 (added 18/10/22) The formula for in the exam report is incorrect. The subsequent formula for is correct. (28/10/23 Now corrected.)
Q10(b) (added 01/11/22) In the second line of the examination report solution, the quantity under the square root sign should be squared.
QB2 (added 24/11/21) – discussed here. A mess of a question. Part (a)(i) makes absolutely no sense, since the writers have forgotten that real numbers are also complex numbers. That then leads to Part (a)(ii) having two distinct solutions. (09/05/22) The report belatedly notes that (a)(ii) has two solutions, but simply lies about the solution to (a)(i). Disgraceful.
QB5 (added 24/11/21) – discussed here. Mostly just an appalling question, but it is worth noting that it’s not great to have a car taking off with infinite acceleration. And, it would be very nice if, some day, someone at VCAA learned what “smoothly” means.
QB6 (added 09/05/22) – discussed here. The preamble to part (c) refers to “main daily sales” rather than “mean daily sales”. The error itself is klutzy but no big deal, and the error is noted in the exam report, albeit in an ass-covering “no students were disadvantaged” manner. The problem is, the published exam has fixed the error, but with no record that there was an error. This is simply not what you do. At least not if you have integrity.
Q9 (added 24/11/21) – discussed here. An absolute mess, with errors. The main error is that the domains of the particles are effectively undefined, but the entire question is appalling. (23/04/22) The exam report is silent on the particles perhaps not colliding, and is silent on the infinitely many correct forms of the answer for part (c)(ii).
QB2(b)(ii) (added 21/10/21) There are infinitely many correct answers of the required form.
Q2 (added 21/10/21) The question confuses whether P is the force or the magnitude of that force; if the latter, which seems to be the intention, then P cannot “act horizontally”, etc.
Q3 (added 21/10/21) – discussed here. Concepts outside the syllabus. Whatever VCAA may now wish to claim, the binomial distribution is not part of the Specialist Mathematics curriculum.
Q5(b) (added 21/10/21) The suggested form of the answer is absurd and leaves infinitely many possibilities.
Q7 (added 21/10/21) The quantity v is never defined.
Q9 Q10 (added 21/10/21) – discussed here. A disastrous question, with no correct answer. The solution in the examination report is complete nonsense. (13/10/22) Commenter E has noted that the first line of the exam report’s solution has an error (even on its own terms).
MCQ2 (added 21/10/21) The suggested approach in the examination report makes no sense.
MCQ9 (added 21/10/21) – discussed here. The question is utterly meaningless.
MCQ11 (added 21/10/21) – discussed here. The question is effectively meaningless. The integral is improper and divergent, meaning that if any answers are considered correct then all of A, C and D should be. The examination report does not acknowledge the issue.
QB3(e)(ii) (added 21/10/21) – discussed here. The question is absurd. The examination report gives absolutely no clue how to go about answering the question.
Q1 (added 02/02/22) – discussed here and here. 1(b) is a mess as worded, and as graded, since the expectation is for students to treat the acceleration as if it were a scalar. In particular, a non-sensical remark in the examination report strongly suggests that students who gave the negative of the report’s answer were invalidly marked down.
Q2 (added 21/10/21) – discussed here. The required form of the answer is meaningless.
Q6 (added 21/10/21) – discussed here and here. A mess. The examination report indicates that in (a) students “needed to demonstrate the use of the chain rule”, which the report’s solution does not do. The “hence” beginning (b) is meaningless and consequently misleading.
Q7(a) (added 21/10/21) The examination report provides no proper indication of what is required for the given function to be continuously differentiable. See the discussion here.
Q8 (added 21/10/21) The required form of the answer is meaningless.
Q9(b) (added 21/10/21) The required form of the answer leaves infinitely many possibilities.
MCQ12 (added 22/10/21) – discussed here. The question is completely meaningless (and intrinsically absurd), involving a vector with a projection of larger magnitude than that of the original vector. The examination report foolishly and dishonestly and cowardly pretends there is some sense in the question. Utterly disgraceful.
QB(1) (added 01/11/21) – discussed here. A confused question, which simply presumes, and expects students to assume, that the relation given in (b) is restricted by the parametrisation given in (a). There is no reason to to assume that, making the answer to (b) in the examination report simply, and arrogantly, wrong. Similarly, (e) as worded is meaningless.
QB(5)(c)(i) (added 012/11/21) – discussed here. The solution in the examination report fails to consider the possibility that m2 > m1 (in which case the angle theta is irrelevant).
QB(6)(f) (added 02/11/21) – discussed here. In itself the question is ok. The issue is, for the corresponding question 6(e) on the 2018 exam, both rounding up and (incorrect) rounding down were accepted, without a word of explanation or warning in the report about future grading policy.
Q9(b) (added 22/10/21) The question involves tension in a ring, which needed to be assumed equal on both sides of the ring. This is a (once upon a time) standard assumption, but apparently many students did not make the assumption. The question states that “The tension in the string has a constant magnitude”, which is further confusing rather than clarifying. The examination report refuses to acknowledge the confusion, sneakily suggesting that “the statement of the question” indicated equal tension on the two sides of the ring; this is dishonest and cowardly.
MCQ 17 (added 01/11/22) The question asks for the maximum height of a thrown ball, but does not specify the initial height of the ball, when thrown. This should have been specified, or the question should have asked for the vertical displacement.
QB(2)(a)(iii) (added 16/11/21) Similar to QB(1)(b) from 2017 Exam 2, below, students are required to graph a function “from x = -6 to x = 6”, and are instructed to “label the asymptotes”. The graph in the examination report goes beyond the specified domain, which, inadvertently, pinpoints the issue; specifying a specific finite domain precludes the possibility of horizontal asymptotes.
Q2(b) (added 22/10/21) – discussed here. The question asks for an answer to 2 decimal places, but the precise answer (using the standard approximation) is 0.025. The examination report states, without explanation, that both 0.02 and 0.03 were accepted as correct.
MCQ3 (added 24/10/21) – discussed here. A badly flawed, and nasty, question. Arguably, there is no correct answer. The comment in the examination report is largely incomprehensible.
QB(3)(f) (added 24/10/21) – discussed here. The question includes concepts outside the syllabus, and the solution in the examination report is incomplete.
QB4(e) (added 24/10/21). The expression “period of time” was slightly ambiguous. It would appear that both the length of time and the time interval were accepted.
QB(6)(a) (added 24/10/21) – discussed here. The examination report implies that a one-tailed test is appropriate in the given scenario. That is far from clear and is better considered false.
QB6(e) (added 06/10/23). Two answers were accepted as correct. The exam report provides no explanation as to why.
Q3 (added 24/10/21) There are infinitely many answers of the correct form.
Q6(b) (added 24/10/21) – discussed here and here. The exam incorrectly asks for a change in momentum in the units kg ms-2. The examination report indicates that a correct calculation of the rate of change of momentum also received full marks. There is not a single word of acknowledgment that, much less apologising for, VCAA having screwed up.
Q8(b) (added 24/10/21) There are infinitely many answers of the correct form.
Q10 (added 24/10/21) – discussed here. There are infinitely many correct answers, and a separate ambiguity. The question is fundamentally flawed, and is simply not asking what VCAA thinks it is asking.
QB(1)(d) (added 24/10/21) – discussed here. The intended approach is valid but very difficult to justify, and is way, way beyond the scope of VCE. The solution involves evaluating an improper integral, which is beyond the scope of VCE, and which is handled poorly by at least one of the standard CAS machines.
Q8(c) (added 24/10/21) The intention was to ask for all rays of the form Arg(z) = α that are perpendicular to a given circle. Instead, the question asked for “the equations of all rays that are perpendicular to the circle in the form Arg(z) = α”. These are not the same.
MCQ10 (added 26/10/21) – discussed here. The question is fundamentally flawed (and is appalling). In particular, depending upon one’s notion of inflection point (which is not defined in the syllabus), it is possible that there are inflection points where f = 0. The examination report is missing a minus sign.
QB(1)(b) (added 15/10/21). The question instructs students to “Sketch the graph of f(x) = x/(1+x3) from x = -3 to x = 3″. Notwithstanding the finite domain, the examination report indicates an asymptote y = 0. There is some ambiguity since, of course, any sketch will be over a finite domain, meaning the indication of an asymptote must be more suggestive than accurate. Nonetheless, the exam instruction to graph the function over a specific finite domain precludes any possibility of a horizontal asymptote. The examination report is clearly in error, and if students were penalised for not having included a horizontal asymptote then this was also an error. (16/10/21)
A lesser issue is that the examination report indicates coordinates of points on the graph to decimal places; this follows on from part (a), but nonetheless violates VCAA’s direction that answers should be exact unless otherwise specified.
QB(4) (added 26/10/21) – discussed here. For (b), the examination report appears to demand an absurd amount of working for the trivial solving of a quadratic equation, and falsely claims that substituting is in invalid method to “show” solutions of an equation. Part (c) is meaningless, and the examination report arrogantly blames the students for not discerning the non-existent meaning. Part (f) is similarly meaningless, but is worse. In sum, an appalling question.
QB(5) (added 26/10/21) – discussed here. The question is a bit of a mess, but it is not clear that there is an error as such. One of the standard machines apparently struggles with (c)(ii). The examination report has an extra √ sign for some reason. (30/10/22) Yes, there is an error. As John Friend has pointed out below, there are two values, , which work, giving two different starting times and starting positions. (The second solution arises from taking ). The exam question indicates the collision occurs “shortly after starting”, which might be used to argue for the earlier of the two starting times, but it’s not enough. There are two entirely separate solutions, each with its own first time of collision reasonably described as “shortly after starting”.
Q2 (added 26/10/21). There are infinitely many answers of the correct form.
Q8(b) (added 26/10/21). There are infinitely many answers of the correct form.
Q10(c) (added 13/11/20) – discussed here. The intended solution requires computing a doubly improper integral, which is beyond the scope of the subject. The examination report ducks the issue, by providing only an answer, with no accompanying solution.
Q3(b) (added 13/11/20) – discussed here. The wording of the question is fundamentally flawed, since the “maximum possible proportion” of the function does not exist here, and in any case need not be equal to the “limiting value” of the function. The examination “report” contains nothing but the intended answer.
Q3 (added 26/10/21) The required form of the answer is absurd, and there are infinitely many answers of this form.
MCQ10 (added 26/10/21) – discussed here. The question is clunky and absurd, and there is no correct answer.
QB(1)(e) (added 26/10/21). The question is poorly written, so there are infinitely many correct answers. (Compare the question discussed here.)
We are not aware of any errors on this exam.
QB(3)(b) (added 26/10/21) The answer is required in an absurd form, and there are infinitely many answers of that form.
Q2 (added 26/10/21) The answers required students to use g = 9.8, rather than g = g, for God only knows what reason.
QB(1)(b) (added 26/10/21) Similar to 2017 and 2019 NHT, once a finite domain has been specified, it is meaningless to talk about horizontal asymptotes.
Q3(b) (added 26/10/21) The “given that” is meaningless.
Q5(b) (added 27/10/21) – discussed here. The question is completely meaningless. The substitution u = x, for example, would perfectly satisfy the parameters of the question.
MCQ6 (added 27/10/21) – discussed here. The question is purely and simply stuffed. The original examination report indicated that all students were awarded the mark but without indicating the error. That has been rectified, although the tense and tone is not exactly overflowing with remorse.
QB(3)(e) (added 27/10/21). A slightly peculiar graphing question, where no particular points were required to be identified. Reportedly, a number of different types of answers were accepted.
Q6 (added 27/10/21) – discussed here. The question is very poorly formed, and is best thought of as wrong.
We are not aware of any errors on this exam.
Q9(b) (added 27/10/21) There are infinitely many answers of the required form.
Q10(b) (added 27/10/21) There are infinitely many answers of the required form.
We are not aware of any errors on this exam.
Q4 (added 27/10/21) The suggested form of the answer is weird (and unnecessary). Presumably, the intention was to specify that k be rational, rather than real.
MCQ11 (added 29/10/21) – discussed here. An absolutely ridiculous, meaningless question.
QB(3)(e) (added 29/10/21) No degree of accuracy was required, which led to weird answers and subsequent answers being accepted.
QB(4) (added 29/10/21) – discussed here. A weird question, the sole purpose of which seems to be to test whether students recognised that . (They didn’t.) Part (c) is meaningless as written, and the solution in the examination report is fundamentally invalid, even for the intended meaning. The use of the (essentially meaningless) term “hybrid function” in (d) and (e) is weird and pointless.
QB(5)(b) (added 29/10/21) There are infinitely many answers of the required form.
Q10 (added 27/10/21) The suggested form of the answer is weird, and there are infinitely many answers of that form.
MCQ2 (added 08/12/23) The question asks for the number of “points in common” of an ellipse and a hyperbola, which is fine (except for being CAS crap). The concern is the exam report, which explains that there are three such points, as follows:
There are two points of intersection and one point where the curves touch. Hence, option D was correct.
This suggests that the examiners are unaware that a point where curves “touch” is also a point of intersection.
MCQ6 (added 29/10/21) – discussed here. Simply screwed. There is no correct answer. The examination report is silent.
MCQ13 (added 24/11/23) The question switches from minutes to seconds as the unit of time.
QB(2)(a) (added 08/12/23) The question, which asks for students to “verify” that a line given by a complex (distance) equation passes through (0,0), is fine. The problem is, the exam report strongly suggests that the question was incorrectly graded. In a seeming criticism, the report notes,
Other [students] assumed the result given in 2b. in their working for 2a.
Given (b) is naturally proven with zero reference to the result of (a), this is a perfectly valid approach.
Q5(c) (added 08/12/23) A nasty, and wrong, question, which evidently stuffed up students. Earlier parts of the question concern a “family of curves” parametrised by k. Then, (c) asks for “the gradient of the curve at the point (1,1)”. This makes no sense, since the specific curve in the family has not been defined (for instance, by declaring that the curve passes through (1,1)). The exam report blithely remarks,
“The majority of students did not realise that the information given fixed the value of k …”
Maybe that’s because it didn’t. The information given simply made no sense, and the students had every reason to have no idea what the hell was going on.
Q9(a) (added 08/12/23) Students are asked to solve “the differential equation”, when what was intended was that students solve the given initial value problem. A toss-up major error. Also (b), on Euler’s method, uses the IVP but not its solution; thus, putting this after (a) is stupid and/or nasty, and it’s clear from the exam report that it screwed up students. (Not an error, just stupid and/or nasty.)
Q10(b) (added 29/10/21) There are infinitely many answers of the required form.
QB(1) (added 30/10/21) Part (b)(i) is weirdly phrased, and is not asking what the examiners think it is asking. There are, for example, infinitely many cubics that correctly answer the question. Similarly, (d)(ii) is not asking what is intended, with infinitely many correct answers.
Q4 (added 30/10/21) The required form is absurd, and there are infinitely many answers of the required form.
MCQ14 (added 01/11/21) A poorly worded and ill-posed question, asking for a differential equation for which “the” solution “models” a population scenario. The question should have asked for the appropriate initial value problem.
QB(1)(d) (added 01/11/21) A fundamentally meaningless question, analogous to B(4)(c) on the 2017 exam, discussed above and here. Interestingly, students performed significantly better on the 2007 exam question, suggesting that the required ritual was reasonably well known in 2007 but had been forgotten by 2017.
Q5(b) (added 31/10/21) There are infinitely many answers of the required form.
Q5(b) (added 31/10/21) The required form is absurd, and there are infinitely many answers of the required form.
MCQ20 (added 24/09/20) The notation refers to the forces in the question being asked, and seemingly also in the diagram for the question, but to the magnitudes of these forces in the suggested answers. The examination report doesn’t acknowledge the error.
Q4(b) (added 24/09/20) There are infinitely many answers of the required form.