unofficiallyred12
Member
- Joined
- Aug 4, 2021
- Messages
- 90
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- Male
- HSC
- 2023
i don't
hopefully the top for mc is 15, iykykAhhh these maths results are making me anxious for the business ones.
Almost ready to go.does anyone know when the solutions for 3u will be going up?
thank you!
Here are the solutions and marks for the 2023 Mathematics Extension 1 BoS trials!
Similar to Mathematics Extension 2, please note that the question paper has been updated (which the solutions are aligned to) with some minor adjustments to a few questions (e.g. split into parts, fixed the mark allocation, edited some wordings). The updated file is attached in my original post of the papers to replace the older version.
...and that wraps up the Maths BoS Trials for another year!
I just want to use this opportunity to thank everyone who helped out for both the Maths exams, including @Paradoxica (for helping with questions and marking), @sharky564 (for helping with questions), @1039213 (for marking), @yanujw (for marking) and @one eight seven (for marking). Also massive thanks to @Carrotsticks for allowing us to hold the events at the Sydney Centre of Mathematics venue.
Watch this space for news on Business Studies and Physics...
business first tho!!can’t wait for physics solutions
Hey mate,Comments for Extension 1, Question 12
(a) (i) I would say about 1/2 of students got this right, the rest would need to revise binomial probability as it was a fairly standard question, and also write out the simultaneous equations to be solved for to avoid silly mistakes.
(ii) There was a surprisingly high amount of non-attempts. For those that gave it a go, a majority didn't understand how to calculate the parameters of each bernoulli trial, and only considered the case where a question was attempted seriously.
Tip: If a question requires the use of the normal approximation and does not give you z-score data, the z-score value that you calculate should always be one that can be solved for with the empirical rule. If you don't get a z-score close to one of the integers -3, -2, -1, 0, 1, 2, 3, recheck your working. The exception is when there is some extra info in the question from which you can derive the values, for example in Question 26 of the 2022 Advanced HSC.
(b) (i) Answer successfully by almost everyone. There was a variety of vector computations used that all worked, such as AP - AB, BO + OP and even a few students that used BC + CP.
(ii) Very, very few marks were awarded across the cohort for this part. Almost every student attempted to use the point Q (i.e. to find BQ or OQ in component form so that they could get the result from dot products) and this was extremely unsuccessful. Only 1 student that used the point Q in this way got 2/2 - but they used 3 pages to complete it! The sophisticated method is to use the geometrical data to your advantage and write POQ in terms of OPQ, noting that the triangle is isosceles, and finding OPQ easily using the dot product of AP and BP, which should be easy from the previous question. In other words, it's worth looking at roundabout geometrical methods that might be easier in the long-run rather than just aiming straight at the result to prove.
(c) (i) Mostly answered successfully, however avoid silly mistakes such as trying to find the cartesian equation of the path - which was redundant in this question, or deriving the displacement vector when it is already provided.
(ii) Only a few students reached 2/2 - most of the others got bogged down in working out and abandoned the process. Try to leave everything in parameters until you need to evaluate it i.e. don't find an expression for R first and sub it in to get a mess of algebra, keep everything as simple as possible.
(d) (i) Most students did the algebra and got the result, nothing more to say here.
(ii) Almost everyone was able to use the previous part, but a common mistake was that the last 3 roots were sin(4pi/7), sin(5pi/7) and sin(6pi/7), implying that there are 3 double roots rather than the negatives of the first 3 roots. A quick sanity check you could've done during the test is to see that the polynomial is even and thus any root that is positive must also be negative, rather than being a double root.
(iii) Done well, with about half the students getting some progress and half of those getting 2/2.
Best of luck for tomorrow's exam!
cheers mateNo. @Trebla will do that at some point so keep an eye out for this thread.
It depends on whether we (still) have people who are prepared to write and mark them. These events are supported by large volunteer efforts. As long as that is sustained and there is student demand for it then we can keep this going in future years.Surely you guys will have a physics one next year as well
hey mate, whens the physics solutions dropping? just finished 3u and would love to sit the paperIt depends on whether we (still) have people who are prepared to write and mark them. These events are supported by large volunteer efforts. As long as that is sustained and there is student demand for it then we can keep this going in future years.
usually they come out a couple days before the hsc, I’d wait to do the paper until thenhey mate, whens the physics solutions dropping? just finished 3u and would love to sit the paper